Laws and cases

The court decisions, laws and rules behind what we cover, in plain language. Click any question to see the answer, what it means for you, and who voted which way. Pick a topic, follow one of the paths below, or search everything.

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The police and your data

When officers need a warrant to get your records from a company, and when they don’t. Start with the third-party doctrine if the idea is new.

Can a state let police bug a room for months on a loosely written court order? (Berger v. New York, 1967)

Berger v. New York1967Still the law

No. New York’s eavesdropping law let officers listen for two months at a time without describing the conversations they were after, so the Court struck it down. An order to bug a room has to be as specific as any other warrant.

What it means for you. It’s why police need a special, time-limited court order to listen to your calls. Congress wrote the federal Wiretap Act a year later to follow Berger and Katz.

Supreme Court, 6–3: Majority: Clark (wrote it), Warren, Douglas, Brennan, Fortas, with Stewart agreeing on the result.
Dissent: Black, Harlan, White.

The case tested New York’s permissive eavesdropping law, which let a judge approve bugging when an officer swore evidence of a crime might turn up. Justice Clark wrote for the Court. Later that year, Katz v. United States extended the same protection to a call from a phone booth.

Wiretap orderA court order letting police listen to calls or conversations as they happen. Federal law requires more for one than for an ordinary search warrant.

U.S. Supreme Court1967388 U.S. 41

Read the opinion^[1]See alsoKatz Warshak

Is it a search when FBI agents record your calls from outside a phone booth, without ever going in? (Katz v. United States, 1967)

Katz v. United States1967Still the law

Yes. The Fourth Amendment protects people, not places, so taping a call from a closed phone booth was a search even though agents never went inside. They needed a warrant first, and because they didn’t get one, the recordings couldn’t be used.

What it means for you. This is the question every new spying tool gets judged by, from thermal cameras to phone tracking: would you reasonably expect privacy?

Supreme Court, 7–1: Majority: Stewart (wrote it), Warren, Douglas, Harlan, Brennan, White, Fortas.
Dissent: Black. Marshall sat out.

Agents taped a listening device to the outside of a public phone booth that Charles Katz used to place illegal bets. The Court overruled Olmstead v. United States (1928), which had said wiretaps weren’t searches because nobody entered the house. Justice Harlan’s concurrence supplied the test later cases adopted.

Reasonable expectation of privacyJustice Harlan’s two-part test: you actually expected privacy, and society is prepared to treat that expectation as reasonable.

U.S. Supreme CourtDecember 18, 1967389 U.S. 3477–1

Read the opinion^[2]See alsoSmith v. Maryland Carpenter Berger

Is it a search when a friend secretly wears a wire for the police? (United States v. White, 1971)

United States v. White1971Still the law

No. When you talk to someone, you take the risk they’ll repeat it to police, and it makes no difference if they record or transmit it as you talk. Police don’t need a warrant to have an informant wear a wire.

What it means for you. Anything you tell a friend can reach the police, recorded or not. The same logic later covered records you give to companies.

Supreme Court, 6–3: Majority: White (wrote it), Burger, Stewart, Blackmun, with Black and Brennan agreeing on the result.
Dissent: Douglas, Harlan, Marshall.

An informant carried a hidden radio transmitter while talking with James White, and agents listened in. Justice Harlan dissented, warning that if police could do this freely, people would have to guard every word they say to anyone.

U.S. Supreme CourtApril 5, 1971401 U.S. 745

Read the opinion^[3]See alsoKatz Smith v. Maryland

Do police need a warrant to record the phone numbers you dial? (Smith v. Maryland, 1979)

Smith v. Maryland1979Still the law, narrowed by Carpenter

No. You give those numbers to the phone company to connect your calls, so you can’t expect them to stay private, and logging them isn’t a search under the Constitution.

What it means for you. It’s why police can get your call logs, and under Miller (1976) your bank records, without a warrant. So far the Supreme Court has carved out only location data.

Supreme Court, 5–3: Majority: Blackmun (wrote it), Burger, White, Rehnquist, Stevens.
Dissent: Stewart, Brennan, Marshall. Powell sat out.

Police suspected Michael Lee Smith of robbing a woman and then making threatening calls to her. Without a warrant, they had the phone company install a pen register on his home line, and it logged a call to her number. The ruling is still why phone, bank and many other records can often be had without a warrant.

Pen registerA device that logs the numbers dialed from a phone line, not what is said on the calls.

U.S. Supreme CourtJune 20, 1979442 U.S. 7355–3

Read the opinion^[4]See alsoKatz Carpenter The third-party doctrine

Can police follow your car on public roads with a hidden tracking beeper? (United States v. Knotts, 1983)

United States v. Knotts1983Still the law

Yes. A car on public roads is out where anyone could watch it, so following its beeper wasn’t a search, and neither was tracking the container to the open fields near Knotts’s cabin. Police didn’t need a warrant.

What it means for you. Anything your car does on public roads is fair game for police. Whether weeks of tracking, as in Jones, or a city full of plate readers changes that is still being fought.

Supreme Court, 9–0: Rehnquist wrote it, joined by Burger, White, Powell and O’Connor. Brennan, Marshall, Blackmun and Stevens agreed with the result in separate opinions.

Officers hid a beeper in a container of chloroform, a chemical used to make drugs, and followed its signal to open fields near Leroy Knotts’s cabin. In United States v. Jones (2012), five justices said a month of GPS tracking is different from following one trip.

BeeperA small radio transmitter hidden in an object so police could follow its signal. GPS trackers have replaced them.

U.S. Supreme Court1983460 U.S. 276

Read the opinion^[5]See alsoJones Schmidt

Can police search the trash you leave at the curb without a warrant? (California v. Greenwood, 1988)

California v. Greenwood1988Still the law

Yes. Once you set garbage out for collection, it’s exposed to the public, from animals and snoops to the collector, so police can take it and go through it without a warrant.

What it means for you. Police use the same logic for other things you throw away or leave behind, like DNA on a discarded cup.

Supreme Court, 6–2: Majority: White (wrote it), Rehnquist, Blackmun, Stevens, O’Connor, Scalia.
Dissent: Brennan, Marshall. Kennedy sat out.

Police in Laguna Beach suspected Billy Greenwood of dealing drugs and had his trash collector turn over his bags. The Court said what you leave out for anyone to pick through isn’t protected, even if you hoped no one would look.

U.S. Supreme CourtMay 16, 1988486 U.S. 356–2

Read the opinion^[6]See alsoSmith v. Maryland Florida v. Jardines

Can police aim a thermal camera at your house from the street without a warrant? (Kyllo v. United States, 2001)

Kyllo v. United States2001Still the law

No. Using a device that isn’t in general public use to learn what’s happening inside a home is a search, even from the street, so police needed a warrant before scanning Kyllo’s house.

What it means for you. Your home is protected from high-tech snooping, but only while the gadget is rare. Once it’s in general public use, this rule may not cover it.

Supreme Court, 5–4: Majority: Scalia (wrote it), Souter, Thomas, Ginsburg, Breyer.
Dissent: Stevens, Rehnquist, O’Connor, Kennedy.

Agents suspected Danny Kyllo of growing marijuana under heat lamps and scanned his house from a car across the street. Justice Scalia wrote for a majority that crossed the usual lines; the dissenters said the scan only measured heat escaping into public view.

General public useThe Court’s caveat. The more common a technology gets, the weaker this protection may become.

U.S. Supreme CourtJune 11, 2001533 U.S. 275–4

Read the opinion^[7]See alsoKatz Jones

Can police walk a drug dog around your car during a traffic stop? (Illinois v. Caballes, 2005)

Illinois v. Caballes2005Still the law

Yes, as long as the stop isn’t dragged out. A sniff that can only reveal contraband isn’t a search, so police need no warrant or suspicion to walk a dog around your car while the stop lasts.

What it means for you. Police can’t stretch a traffic stop to wait for the dog, though. That needs its own reason to suspect you, said Rodriguez v. United States (2015).

Supreme Court, 6–2: Majority: Stevens (wrote it), O’Connor, Scalia, Kennedy, Thomas, Breyer.
Dissent: Souter, Ginsburg. Rehnquist sat out.

Roy Caballes was stopped for speeding on an Illinois interstate. A second trooper arrived with a dog, which alerted on his trunk, and officers found marijuana. The Court reasoned that no one has a legitimate privacy interest in contraband.

U.S. Supreme CourtJanuary 24, 2005543 U.S. 4056–2

Read the opinion^[8]See alsoFlorida v. Jardines Kyllo

Can the government read your email by getting it from your provider without a warrant? (United States v. Warshak, 2010)

United States v. Warshak2010Still the law in the Sixth Circuit

No. You have a reasonable expectation of privacy in what your emails say, even though a company stores them, so the government needs a warrant to make the provider turn them over.

What it means for you. It treats your email like a sealed letter, not a dialed number. Big email providers now demand a warrant before turning over messages.

Sixth Circuit: Judge Danny Boggs wrote it.

Prosecutors building a fraud case over Steven Warshak’s supplement company got about 27,000 of his emails from his provider with an order under the Stored Communications Act instead of a warrant. The court held that part of the law unconstitutional, but let the emails in because officers had relied on it in good faith.

Stored Communications ActThe 1986 law that sets the rules for police getting records and messages from email and internet companies.

U.S. Court of Appeals for the Sixth CircuitDecember 14, 2010631 F.3d 266

Find the opinion^[9]See alsoSmith v. Maryland Chatrie

Is attaching a GPS tracker to your car and following it for a month a search? (United States v. Jones, 2012)

United States v. Jones2012Still the law

Yes. Attaching the tracker to the car was itself a search, so police needed a warrant they didn’t have. Five justices added that a month of GPS tracking would be a search even without touching the car.

What it means for you. One drive is public; a month of drives shows where you worship and which doctors you see. Carpenter built on that idea.

Supreme Court, 9–0: Scalia wrote it, joined by Roberts, Kennedy, Thomas and Sotomayor. Alito, Ginsburg, Breyer and Kagan agreed with the result for a different reason: a month of tracking is too long.

Police put a GPS device on a Jeep used by Antoine Jones, a nightclub owner suspected of drug trafficking, and tracked it for 28 days. Justice Scalia’s majority rested on trespass. Justice Sotomayor went further and questioned the third-party doctrine itself in the digital age.

Mosaic theoryThe idea that many small observations, added together, can reveal a whole life even when no single one would.

U.S. Supreme CourtJanuary 23, 2012565 U.S. 4009–0

Read the opinion^[10]See alsoKyllo Carpenter Knotts

Can police bring a drug dog to your front door without a warrant? (Florida v. Jardines, 2013)

Florida v. Jardines2013Still the law

No. Your front porch counts as part of your home, and bringing a drug dog onto it goes beyond what any visitor may do. Anyone can walk up and knock; police can’t bring a dog to hunt for evidence without a warrant.

What it means for you. Homes get the strongest protection. A sniff that’s fine at a traffic stop becomes a search on your porch.

Supreme Court, 5–4: Majority: Scalia (wrote it), Thomas, Ginsburg, Sotomayor, Kagan.
Dissent: Alito, Roberts, Kennedy, Breyer.

Miami-Dade police got a tip about marijuana in Joelis Jardines’s house and brought a trained dog to his front door, where it alerted. Justice Scalia wrote that anyone may approach a house and knock, but not with a dog trained to search.

CurtilageThe area right around a home, like a porch or yard, that the law treats as part of the home itself.

U.S. Supreme CourtMarch 26, 2013569 U.S. 15–4

Read the opinion^[11]See alsoIllinois v. Caballes Kyllo

Can police search your phone when they arrest you? (Riley v. California, 2014)

Riley v. California2014Still the law

Not without a warrant. Officers can take your phone and check that it isn’t a weapon, but the data needs a warrant, because a phone holds so much of your life. Only a real emergency is an exception.

What it means for you. If police ask to look through your phone after an arrest, you can say no. Without your consent, they need a warrant unless it’s a real emergency.

Supreme Court, 9–0: Roberts wrote it for all nine. Alito added a separate concurrence.

David Riley was stopped for expired registration tags; officers found guns in his car and gang-related photos and videos on his smartphone. The Court decided his case together with United States v. Wurie, about a flip phone. Chief Justice Roberts’ answer to police was short: get a warrant.

U.S. Supreme CourtJune 25, 2014573 U.S. 3739–0

Read the opinion^[12]See alsoCarpenter

Can police get months of your phone’s location records from your carrier without a warrant? (Carpenter v. United States, 2018)

Carpenter v. United States2018Still the law

No. Getting those records is a search, so police generally need a warrant, even though the phone company holds them. A detailed record of where you go isn’t like the bank records and dialed numbers in older cases.

What it means for you. Your carrier logs everywhere your phone goes. Carpenter first said that giving data to a company isn’t giving it to police.

Supreme Court, 5–4: Majority: Roberts (wrote it), Ginsburg, Breyer, Sotomayor, Kagan.
Dissent: Kennedy, Thomas, Alito, Gorsuch, in four separate dissents.

Police used 127 days of records from Timothy Carpenter’s carriers to place his phone near a string of store robberies. Chief Justice Roberts wrote that a detailed record of where someone goes is different from the bank records and dialed numbers in the older cases. The Court called the decision narrow and left things like security camera footage for another day.

Cell-site location recordsThe log of which towers your phone connected to, and when. Carriers keep it whether or not you use location services.

U.S. Supreme CourtJune 22, 2018585 U.S. 2965–4

Read the opinion^[13]See alsoChatrie The third-party doctrine

Can police make Google turn over everyone who searched for certain words? (Commonwealth v. Kurtz, 2025)

Commonwealth v. Kurtz2025Still the law in Pennsylvania

In Pennsylvania, yes. The state’s top court upheld a warrant that made Google name everyone who searched certain words, and three justices went further: ordinary Google searches aren’t constitutionally private.

What it means for you. Chatrie protects where you go. In Pennsylvania, what you type into Google is still open to police.

Pennsylvania Supreme Court, 6–1: Justice Wecht wrote the lead opinion, for three justices. Chief Justice Todd and Justice Mundy agreed with the result, saying the warrant had probable cause.
Dissent: Justice Donohue.

A keyword warrant runs backwards from a normal one. Police don’t name a person; they name the search terms, and Google names the people who typed them. A search engine that never kept your searches has nothing to turn over, which is why our search picks matter here.

Keyword warrantA warrant that names search terms instead of a suspect, and asks a company who searched for them.

Pennsylvania Supreme CourtDecember 16, 202598 MAP 20236–1

Find the opinion^[14]See alsoChatrie

Is a city-wide network of plate-reader cameras a Fourth Amendment search? (Schmidt v. City of Norfolk, 2026)

Schmidt v. City of Norfolk2026On appeal

Not according to the trial judge. He upheld Norfolk’s 176 Flock cameras because snapshots at intersections can’t capture the whole of anyone’s movements. The case is now on appeal, and the Fourth Circuit has it tentatively set for argument in its December 8–11, 2026 session.

What it means for you. Plate readers like the ones around Pitt photograph your car every time you pass one, building a record of where you drive.

One federal judge: Judge Mark Davis decided it. Trial courts have one judge, so there’s no vote.

Chatrie also gives Norfolk something to work with: the Supreme Court separated phone data, which follows you indoors, from plate readers that only see public roads. The Fourth Circuit, the same court the Supreme Court reversed in Chatrie, now has to sort that out.

U.S. District Court, Eastern District of VirginiaJanuary 27, 2026On appeal to the Fourth Circuit; argument expected Dec. 2026

The case page^[15]See alsoOur plate-reader campaign Chatrie Knotts

Is it a Fourth Amendment search when police make Google turn over your location history, even two hours of it? (Chatrie v. United States, 2026)

Chatrie v. United States2026Sent back to the Fourth Circuit

Yes. Your location record stays protected even when a company holds it, and two hours is enough to count. Whether this particular warrant was good enough is a separate question, which the Court sent back to the Fourth Circuit.

What it means for you. Google says your Timeline is now stored only on your phone, so it can’t answer these warrants anymore. Police who want location data from other apps generally need a warrant.

Supreme Court, 6–3: Majority: Kagan (wrote it), Roberts, Sotomayor, Kavanaugh, Jackson, with Gorsuch agreeing on the result for property reasons.
Dissent: Alito, Thomas, Barrett.
Fourth Circuit, before: The full appeals court split evenly, which left Chatrie’s conviction in place.

Police investigating a 2019 credit-union robbery in Midlothian, Virginia, served Google a warrant in steps: anonymous location data for 19 accounts near the scene, then two hours of movements for some of them, then names, including Chatrie’s. Justice Kagan wrote for five justices, and Justice Gorsuch supplied the sixth vote on property grounds. The Court didn’t decide whether geofence warrants are always unconstitutional, as the Fifth Circuit has held, or whether the evidence gets thrown out.

Geofence warrantA warrant for every device in an area during a time window, instead of for one named suspect.

In practice, this kind of warrant has mostly stopped working on Google. It had spread fast: Google got its first geofence warrant in 2016 and more than 11,000 in 2020. In December 2023 Google said it would store Location History, now called Timeline, on people’s phones instead of its servers. By July 2025, it told the Court, everything on its servers had been deleted or moved to devices, so it can no longer answer geofence warrants for that data. Other apps and companies still collect location data, your searches are a different story (see Kurtz), and plate readers, which only watch public roads, are still open (see Schmidt).

TimelineGoogle Maps’ record of where you’ve been, formerly Location History. Google says it now keeps it only on your device.

U.S. Supreme CourtJune 29, 2026No. 25-1126–3

Read the opinion^[16]See alsoCarpenter Kurtz Schmidt

Next: Spying and national security

Spying and national security

Programs approved by a secret court and hard to challenge, because you usually can’t prove you were watched.

Can the government wiretap a suspected spy without a regular warrant? (Foreign Intelligence Surveillance Act, 1978)

Foreign Intelligence Surveillance Act1978In force, expanded since

Yes, with an order from a secret court. FISA lets the government watch a foreign power or its agent once a special court finds probable cause, usually hearing only the government’s side. It doesn’t have to show a crime is being committed.

What it means for you. Your calls or messages can be collected if you talk with someone the government targets, under secret orders from a court that usually hears only the government’s side.

Congress, 1978: Senate 95–1, House 246–128. President Carter signed it on October 25, 1978.

Senator Frank Church’s committee found the NSA and other agencies had spied on Americans for years. FISA set up a special court of federal judges to approve national-security surveillance. The USA PATRIOT Act of 2001 loosened it from requiring that foreign intelligence be the purpose to requiring only a significant purpose, and the FISA Amendments Act of 2008 added Section 702.

FISA courtA special court of federal judges that approves surveillance orders in secret, usually hearing only from the government.

Act of CongressOctober 25, 197850 U.S.C. § 1801 and following

Read the law^[17]See alsoClapper Hasbajrami

Could AT&T customers sue the company for helping the NSA copy their internet traffic? (Hepting v. AT&T, 2006)

Hepting v. AT&T2006Dismissed after Congress granted immunity

No, in the end. The judge refused to throw the case out on state-secrets grounds, but in 2008 Congress gave phone companies retroactive immunity, and the suit was dismissed.

What it means for you. If a phone company helps the government spy on you, Congress can take away your right to sue after the fact, as it did here.

Congress, 2008: Granted the immunity in the FISA Amendments Act: House 293–129, Senate 69–28. An amendment to strip the immunity out failed 32–66.

AT&T technician Mark Klein described a secret room in the company’s San Francisco building where copies of internet traffic were routed to the NSA. Customers, represented by EFF, sued in 2006. The Ninth Circuit upheld the immunity in 2011.

Retroactive immunityA law passed after the fact that wipes out liability for what a company already did.

U.S. District Court, Northern District of CaliforniaFiled January 31, 2006Dismissed 2009

Find the case^[18]See alsoClapper v. Amnesty ACLU v. Clapper

Can lawyers and journalists challenge a secret surveillance program they believe is sweeping up their calls? (Clapper v. Amnesty International USA, 2013)

Clapper v. Amnesty International USA2013Still the law

Not without proof. They lacked standing because they couldn’t show their calls would be intercepted, and a reasonable fear of surveillance, or money spent avoiding it, wasn’t enough.

What it means for you. A catch-22: to sue over secret surveillance, you have to prove you were watched. Four months later, Snowden’s documents showed how wide it was.

Supreme Court, 5–4: Majority: Alito (wrote it), Roberts, Scalia, Kennedy, Thomas.
Dissent: Breyer, Ginsburg, Sotomayor, Kagan.
Congress, 2008: The law they challenged, the FISA Amendments Act, passed the House 293–129 and the Senate 69–28.

Amnesty International, along with lawyers, journalists and human-rights groups, sued over the FISA Amendments Act of 2008, which created Section 702. Justice Alito wrote that their injury was too speculative, and that money they spent protecting their communications didn’t count either.

Section 702It lets intelligence agencies collect foreigners’ communications without individual warrants. Americans’ messages get swept up too.

U.S. Supreme CourtFebruary 26, 2013568 U.S. 3985–4

Read the opinion^[19]See alsoBills and rules we track FISA

Did the Patriot Act let the NSA collect records of nearly every phone call Americans made? (ACLU v. Clapper, 2015)

ACLU v. Clapper2015Program ended by Congress weeks later

No. Section 215 allowed records “relevant” to an investigation, and the court said that word couldn’t stretch to cover everyone’s calls. Congress ended bulk collection weeks later.

What it means for you. Your phone records aren’t collected in bulk anymore. The NSA now has to ask phone companies for specific records, case by case.

Congress, 2015: Ended bulk collection with the USA FREEDOM Act: House 338–88, Senate 67–32. President Obama signed it on June 2, 2015.

The program gathered metadata rather than the content of calls, but the court noted how much metadata can reveal. Section 215 itself expired in 2020.

MetadataWho called whom, when, and for how long, but not what was said.

U.S. Court of Appeals for the Second CircuitMay 7, 2015785 F.3d 787

Find the opinion^[20]See alsoSmith v. Maryland Clapper v. Amnesty

Can the FBI search spy data collected on foreigners for an American’s messages without a warrant? (United States v. Hasbajrami, 2019)

United States v. Hasbajrami2019On appeal again

Not freely. The Second Circuit held in 2019 that these backdoor searches are separate Fourth Amendment events, and in 2025 the trial judge ruled that the ones in this case needed a warrant.

What it means for you. If you talk to people abroad, your messages can land in the Section 702 pile, and the FBI can search that pile for Americans’ names.

Agron Hasbajrami, a U.S. resident, was arrested at JFK Airport in 2011 on his way to Pakistan and charged with trying to support terrorists. He had already pleaded guilty when the government revealed it had used Section 702. The 2025 ruling still let the evidence stand on separate grounds, and the case is back before the Second Circuit.

Backdoor searchQuerying data collected under Section 702 with an American’s name, email address or other identifier.

Second Circuit, December 18, 2019E.D.N.Y., January 21, 2025945 F.3d 641

Find the 2019 opinion^[21]See alsoClapper v. Amnesty ACLU v. Clapper

Next: Speech online

Speech online

How the First Amendment works online: incitement, threats, indecency, library filters, anonymous speech, lies, voter intimidation, and age checks.

When can the government punish someone for advocating violence or lawbreaking? (Brandenburg v. Ohio, 1969)

Brandenburg v. Ohio1969Still the law

Only for incitement: speech meant to produce imminent lawless action that is likely to. Advocating force or lawbreaking in the abstract, even at a Klan rally, is protected.

What it means for you. It’s the test for extreme speech online too: an angry post isn’t a crime unless it’s aimed at, and likely to cause, lawbreaking right away.

Supreme Court, unanimous: An unsigned opinion for the whole Court. Black and Douglas each added a concurrence.

Clarence Brandenburg, a Ku Klux Klan leader, was convicted under Ohio’s criminal syndicalism law for a filmed rally speech. The Court overturned the conviction and overruled Whitney v. California (1927), replacing the older clear-and-present-danger approach.

Imminent lawless actionSpeech aimed at producing lawbreaking right away, and likely to, rather than at some point in the future.

U.S. Supreme CourtJune 9, 1969395 U.S. 444

Read the opinion^[22]See alsoHate speech

What makes something legally obscene, and so unprotected by the First Amendment? (Miller v. California, 1973)

Miller v. California1973Still the law

Material that fails a three-part test: judged by community standards, it appeals to a prurient interest, shows sexual conduct in a patently offensive way, and lacks serious literary, artistic, political or scientific value. Most sexual material passes.

What it means for you. Most sexual material online isn’t legally obscene, so it’s protected speech for adults. Which town’s standards decide the rest still isn’t settled.

Supreme Court, 5–4: Majority: Burger (wrote it), White, Blackmun, Powell, Rehnquist.
Dissent: Douglas, Brennan, Stewart, Marshall.

Marvin Miller was convicted after mass-mailing brochures advertising adult books to people who hadn’t asked for them. Most sexually explicit material isn’t obscene under this test, which reaches only a narrow band of hard-core material.

U.S. Supreme CourtJune 21, 1973413 U.S. 155–4

Read the opinion^[23]See alsoReno v. ACLU Free Speech Coalition v. Paxton

Can the government punish a radio station for airing indecent words in the afternoon? (FCC v. Pacifica Foundation, 1978)

FCC v. Pacifica Foundation1978Still the law for broadcasting

Yes. Broadcasting reaches into homes and is easy for children to hear, so the FCC can restrict indecent material during the day even when it isn’t obscene.

What it means for you. It’s why broadcast TV and radio bleep words the internet doesn’t have to. Reno v. ACLU refused to carry this rule online.

Supreme Court, 5–4: Majority: Stevens (wrote it), Burger, Rehnquist, Powell, Blackmun.
Dissent: Brennan, Stewart, White, Marshall.

A New York station aired George Carlin’s “Filthy Words” monologue at 2 p.m., and a man who heard it in the car with his young son complained to the FCC. The ruling is why broadcasters keep indecent material to late-night hours.

U.S. Supreme CourtJuly 3, 1978438 U.S. 7265–4

Read the opinion^[24]See alsoReno v. ACLU Miami Herald v. Tornillo

Can a state ban anonymous campaign leaflets? (McIntyre v. Ohio Elections Commission, 1995)

McIntyre v. Ohio Elections Commission1995Still the law

No. Choosing to stay anonymous is part of free speech, so Ohio couldn’t fine Margaret McIntyre for handing out unsigned leaflets about a school tax.

What it means for you. It’s why the government can’t make you sign your political speech, online or off. Doe v. Cahill built on it.

Supreme Court, 7–2: Majority: Stevens (wrote it), O’Connor, Kennedy, Souter, Thomas, Ginsburg, Breyer.
Dissent: Scalia, Rehnquist.

Margaret McIntyre handed out leaflets against a school tax levy, signed “Concerned Parents and Tax Payers,” and was fined $100. Justice Stevens called anonymity a shield from the tyranny of the majority, building on Talley v. California (1960), which struck down a ban on anonymous handbills.

U.S. Supreme CourtApril 19, 1995514 U.S. 3347–2

Read the opinion^[25]See alsoDoe v. Cahill

Can Congress ban indecent material online to protect kids? (Reno v. ACLU, 1997)

Reno v. ACLU1997Still the law

Not the way the Communications Decency Act did. The Court struck down its indecency rules because the internet gets full First Amendment protection, not the looser rules for broadcast TV and radio, and the law would have silenced speech adults have a right to.

What it means for you. It’s why no agency can fine a website for swearing the way the FCC fines broadcasters. Section 230, passed in the same law, survived.

Supreme Court, 7–2: Majority: Stevens (wrote it), Scalia, Kennedy, Souter, Thomas, Ginsburg, Breyer. O’Connor and Rehnquist agreed in part and dissented in part.
Congress, 1996: The CDA rode in the Telecommunications Act, which passed the House 414–16 and the Senate 91–5 on February 1, 1996.

The 1996 law made it a crime to send “indecent” or “patently offensive” material where minors could see it. Justice Stevens wrote that the internet isn’t scarce or invasive the way broadcasting is, and that the law would have suppressed a large amount of speech adults have a right to.

Indecent and obsceneObscene material has no First Amendment protection. Indecent material does, at least for adults.

U.S. Supreme CourtJune 26, 1997521 U.S. 844

Read the opinion^[26]See alsoFree Speech Coalition v. Paxton Zeran v. AOL

Can a public library put blocking software on every computer, for adults too? (Mainstream Loudoun v. Board of Trustees, 1998)

Mainstream Loudoun v. Board of Trustees1998Narrowed by the Supreme Court in 2003

Not the way Loudoun County did. Filtering every computer, for adults too, restricted speech based on its content more than necessary, and the library hadn’t tried lighter options like filtering only children’s terminals.

What it means for you. Library computers are how many people get online for free. In 2003 the Supreme Court let Congress require filters there, since adults can ask to switch them off.

One federal judge: Judge Leonie Brinkema decided it.

The library chose X-Stop, a commercial filter that blocked sites like the Quaker home page and Zero Population Growth. Judge Leonie Brinkema pointed to alternatives such as privacy screens and filtering only the computers children use.

U.S. District Court, Eastern District of VirginiaNovember 23, 199824 F. Supp. 2d 552

Find the opinion^[27]See alsoReno v. ACLU Free Speech Coalition v. Paxton U.S. v. American Library Ass’n

Can Congress ban sexual images that only appear to show minors, when no real child was involved? (Ashcroft v. Free Speech Coalition, 2002)

Ashcroft v. Free Speech Coalition2002Still the law

Not that broadly. The Court struck down parts of the Child Pornography Prevention Act because they reached images made without any real child, including computer-generated ones and adult actors who look young.

What it means for you. Images of real children are still illegal; Congress answered with the narrower PROTECT Act in 2003. AI-generated images have put this case back in the debate.

Supreme Court, 6–3: Majority: Kennedy (wrote it), Stevens, Souter, Ginsburg, Breyer, with Thomas agreeing on the result.
Dissent: Rehnquist, O’Connor and Scalia, at least in part.

Justice Kennedy noted the law could have covered films like Traffic and American Beauty. The government argued virtual images could still be used to lure children or to hide real abuse; the Court held those harms didn’t justify banning protected speech.

OverbreadthA law falls if it bans a substantial amount of protected speech along with what it’s allowed to ban.

U.S. Supreme CourtApril 16, 2002535 U.S. 234

Read the opinion^[28]See alsoReno v. ACLU Age verification and ID

Can Congress make libraries filter the internet to keep their federal funding? (United States v. American Library Association, 2003)

United States v. American Library Association2003Still the law

Yes. The Court upheld the Children’s Internet Protection Act, which ties federal internet money to filters, partly because adults can ask a librarian to turn the filter off.

What it means for you. It’s why public library and school computers usually come filtered. If you’re an adult and a library filter blocks something you need, you can ask to have it turned off.

Supreme Court, 6–3: Majority: Rehnquist (wrote the lead opinion), O’Connor, Scalia, Thomas, with Kennedy and Breyer agreeing on the result.
Dissent: Stevens, Souter, Ginsburg.

Congress passed the law in December 2000, tying two federal programs that help schools and libraries pay for internet access to installing filters. The libraries argued that filters wrongly block lawful sites. The plurality compared filtering to a library choosing which books to buy.

CIPAThe Children’s Internet Protection Act. Schools and libraries that take certain federal internet money have to filter their computers.

U.S. Supreme Court2003539 U.S. 194

Read the opinion^[29]See alsoMainstream Loudoun Reno v. ACLU

Can record labels make an internet provider name the customers they accuse of file sharing? (Sony Music Entertainment v. Does 1–40, 2004)

Sony Music Entertainment v. Does 1–402004Still cited

Here, yes. Sharing music files is a kind of expression, but it gets little protection, and the labels showed a real case, so Cablevision had to identify the users.

What it means for you. Your provider knows which customer had which address. When someone sues over what that address did, this kind of test decides whether your name is turned over.

One federal judge: Judge Denny Chin decided it.

Seventeen record companies sued 40 unnamed people for sharing songs over a peer-to-peer network, then subpoenaed Cablevision for their names. Four of them asked the court to block the subpoena. Judge Denny Chin weighed how strong the labels’ case was, whether there was another way to get the names, and how much privacy the users could expect.

SubpoenaA court order to turn over information or testify. Here, an order telling an internet provider to name its customers.

U.S. District Court, Southern District of New York2004326 F. Supp. 2d 556

Find the decision^[30]See alsoDoe v. Cahill A&M Records v. Napster

Can Pennsylvania make internet providers block websites the attorney general flags as child pornography? (Center for Democracy and Technology v. Pappert, 2004)

Center for Democracy and Technology v. Pappert2004Still the law

Not this way. Blocking whole addresses cut off more than 1.19 million sites that were never targeted, so the law swept in far too much protected speech and was struck down.

What it means for you. When a state forces your internet provider to block sites, lawful ones you use get caught too, because one address can host thousands of sites.

One federal judge: Judge Jan DuBois decided it, in Philadelphia.

Pennsylvania passed its Internet Child Pornography Act in February 2002. The attorney general sent providers informal notices listing sites, and providers blocked them with methods that couldn’t separate one site from the others sharing its address. Judge Jan DuBois struck the law down.

OverblockingWhen a filter or block cuts off lawful sites along with the ones it was aimed at.

U.S. District Court, Eastern District of Pennsylvania2004337 F. Supp. 2d 606

Find the decision^[31]See alsoU.S. v. American Library Ass’n Reno v. ACLU

What does someone have to show before a court unmasks an anonymous online critic? (Doe v. Cahill, 2005)

Doe v. Cahill2005Still the law in Delaware

Real evidence. Before a provider is forced to reveal who posted, the plaintiff needs a case strong enough to survive summary judgment, and has to try to warn the poster first so they can respond.

What it means for you. Without a bar like this, anyone could unmask a critic just by filing a weak defamation suit.

Delaware Supreme Court: Chief Justice Myron Steele wrote it.

A town councilman in Smyrna, Delaware, sued an anonymous blogger who called him paranoid and wrote about his “mental deterioration,” and asked Comcast to identify the poster. The court said no reasonable reader would take the comments as statements of fact, and blocked the unmasking.

UnmaskingA court order making a website or internet provider reveal who is behind an anonymous account.

Delaware Supreme CourtOctober 5, 2005884 A.2d 451

Find the opinion^[32]See alsoMcIntyre Sony Music v. Does

Can the government make it a crime to lie about winning a military medal? (United States v. Alvarez, 2012)

United States v. Alvarez2012Still the law

Not by banning the lie alone. The Court struck down the Stolen Valor Act because falsehood by itself doesn’t strip speech of protection. Lies tied to specific harms, like fraud and perjury, can still be punished.

What it means for you. Lying alone isn’t a crime here. That’s why misinformation laws are hard to write, and why Mackey was charged with conspiracy, not lying.

Supreme Court, 6–3: Majority: Kennedy (wrote the lead opinion), Roberts, Ginsburg, Sotomayor, with Breyer and Kagan agreeing on the result.
Dissent: Alito, Scalia, Thomas.

Xavier Alvarez introduced himself at a water district board meeting by falsely claiming the Medal of Honor. No opinion won a majority: four justices used the most demanding test, and two concurred using a softer one, which is part of why the rules on lies are still unsettled.

U.S. Supreme CourtJune 28, 2012567 U.S. 7096–3

Read the opinion^[33]See alsoUnited States v. Mackey

Can people who send robocalls scaring voters away from mail-in voting be held responsible? (National Coalition on Black Civic Participation v. Wohl, 2023)

National Coalition on Black Civic Participation v. Wohl2023Ended in a consent decree

Yes. A federal judge held Jacob Wohl and Jack Burkman liable for intimidating voters, and said the First Amendment didn’t protect calls designed to make people afraid to vote.

What it means for you. If someone tries to scare you out of voting, you can sue them yourself. Voters in New York, Pennsylvania and Ohio did, and won.

One federal judge: Judge Victor Marrero decided it.

In August 2020, the two sent about 85,000 robocalls aimed at Black voters in New York, Pennsylvania, Ohio, Michigan and Illinois. The calls said that voting by mail would let police track people down, help debt collectors find them, and let the CDC use their information for forced vaccines. Judge Victor Marrero ruled for the voters and New York’s attorney general under the Voting Rights Act and the Ku Klux Klan Act. The two also pleaded guilty to telecommunications fraud in Ohio, and later agreed to a consent decree here.

Voter intimidationThreatening or scaring people to keep them from voting. Section 11(b) of the Voting Rights Act bans it.

U.S. District Court, Southern District of New YorkMarch 8, 2023No. 20-cv-8668

Read the decision^[34]See alsoUnited States v. Mackey Counterman v. Colorado

Can you be convicted for threatening messages if you didn’t realize they sounded like threats? (Counterman v. Colorado, 2023)

Counterman v. Colorado2023Still the law

Not unless you were at least reckless: you knew there was a real chance people would see your words as a threat, and sent them anyway. A state can’t convict based only on how a reasonable person would read them.

What it means for you. Online, a joke, a lyric and a threat can look alike in a screenshot. This sets how much the sender must understand before a post can be punished as a threat.

Supreme Court, 7–2: Majority: Kagan (wrote it), Roberts, Alito, Kavanaugh, Jackson, with Sotomayor and Gorsuch agreeing on the result.
Dissent: Barrett, Thomas.

Billy Counterman sent hundreds of Facebook messages over two years to a singer-songwriter he had never met, and kept opening new accounts when she blocked him. Colorado convicted him of stalking under a test that only asked how a reasonable person would read the messages. Justice Kagan wrote for the Court, which sent the case back.

RecklessnessKnowing there’s a real risk your words will be taken as a threat, and sending them anyway.

U.S. Supreme Court2023600 U.S. 66

Find the opinion^[35]See alsoHate speech Brandenburg

Can a state make porn sites check users’ ages? (Free Speech Coalition v. Paxton, 2025)

Free Speech Coalition v. Paxton2025Still the law

Yes. The Court upheld Texas’s age-verification law under intermediate scrutiny, holding that adults have no right to avoid age checks for material that’s obscene for minors.

What it means for you. States can now make adult sites check your age, which usually means uploading your ID or a scan of your face. For two decades, courts had blocked laws like this.

Supreme Court, 6–3: Majority: Thomas (wrote it), Roberts, Alito, Gorsuch, Kavanaugh, Barrett.
Dissent: Kagan, Sotomayor, Jackson.

Congress’s own attempt, the Child Online Protection Act, never took effect: in Ashcroft v. ACLU (2004) the Court said filtering software might protect kids with less burden on adults, and lower courts later struck the law down. In Paxton, Justice Kagan, joined by Justices Sotomayor and Jackson, dissented and argued for the strictest test.

Intermediate scrutinyA middle test: the law has to serve an important interest without burdening much more speech than it needs to.

U.S. Supreme CourtJune 27, 2025No. 23-11226–3

Find the opinion^[36]See alsoReno v. ACLU Age verification

Can posting fake voting instructions be prosecuted as a conspiracy against voters’ rights? (United States v. Mackey, 2025)

United States v. Mackey2025Conviction overturned

Possibly, but not on this evidence. The court assumed the law could reach lies about how to vote, then reversed Douglass Mackey’s conviction because prosecutors never showed he knowingly agreed with anyone to spread them. Posting the memes on his own wasn’t a conspiracy.

What it means for you. No state lets you vote by text, so a post saying you can is a lie. Whether one person telling that lie alone is a federal crime is still open.

Second Circuit, 3–0: Chief Judge Debra Ann Livingston wrote it, joined by Judges Reena Raggi and Beth Robinson.

On November 1 and 2, 2016, Mackey posted or reposted three memes on Twitter telling Hillary Clinton’s supporters they could vote by texting “Hillary” to 59925. About 5,000 people texted the number; about 98 percent got an automatic reply saying it wasn’t the campaign, and prosecutors offered no evidence that Mackey’s posts tricked anyone out of voting.

Fake ad tweeted by @TheRickyVaughn with the hashtags #ImWithHer and #GoHillary. A woman stands in front of an “African Americans for Hillary” sign beside the text: Avoid the line. Vote from home. Text ‘Hillary’ to 59925. Vote for Hillary and be a part of history. — The meme Mackey tweeted on November 1, 2016, made to look like a Clinton campaign ad. From the Second Circuit’s opinion, page 12 (record cite A-371).

A jury convicted him in 2023 under a Reconstruction-era law against conspiring to injure people’s rights. The government’s theory was a plan hatched in private Twitter group chats it called the War Room, but it conceded he downloaded the memes from 4chan, and the court found that just as consistent with him acting alone. Even a brief on Mackey’s side, Eugene Volokh’s, said a narrow ban on knowing lies about how to vote would be constitutional.

Section 241An 1870 law that makes it a crime for two or more people to conspire to injure anyone’s exercise of a right, including voting.

U.S. Court of Appeals for the Second CircuitJuly 9, 2025No. 23-7577

Read the decisionSee alsoUnited States v. Alvarez Murthy v. Missouri National Coalition v. Wohl

Next: Platforms and the law

Platforms and the law

Whether platforms are bound by the First Amendment, who answers for what users post and what feeds recommend, how far the government can lean on them, and the rules for the companies that carry your traffic.

Can a private company that runs a whole town ban people from handing out leaflets? (Marsh v. Alabama, 1946)

Marsh v. Alabama1946Still the law, rarely applied

No. A company town that works like a public one has to respect the First Amendment, even on its own property, so Grace Marsh couldn’t be arrested for handing out religious literature on its sidewalk.

What it means for you. If a platform takes down your post, the First Amendment usually doesn’t help you: private companies aren’t bound by it, even when they act like a town square.

Supreme Court, 5–3: Majority: Black (wrote it), Douglas, Murphy, Rutledge, Frankfurter.
Dissent: Reed, Stone, Burton. Jackson sat out.

Grace Marsh, a Jehovah’s Witness, was arrested for trespassing while handing out literature in Chickasaw, Alabama, a town owned by a shipbuilding company. Later cases about shopping malls first extended Marsh, in Amalgamated Food Employees v. Logan Valley Plaza (1968), then pulled back in Lloyd Corp. v. Tanner (1972) and Hudgens v. NLRB (1976).

State actionThe First Amendment limits the government, not private companies, unless a company is doing the government’s job or acting at its direction.

U.S. Supreme CourtJanuary 7, 1946326 U.S. 5015–3

Read the opinion^[37]See alsoMiami Herald v. Tornillo Murthy v. Missouri

Can a city dodge anti-discrimination rules by turning a public park over to private trustees? (Evans v. Newton, 1966)

Evans v. Newton1966Still the law

No. A park that serves the public keeps its public character, so swapping in private trustees couldn’t let it stay whites-only.

What it means for you. A city can’t escape the Constitution by turning a public place over to private managers, so your rights there come with it.

Supreme Court, 6–3: Majority: Douglas (wrote it), Warren, Clark, Brennan, Fortas, with White agreeing on the result.
Dissent: Black, Harlan, Stewart.

Senator Augustus Bacon left land to Macon, Georgia, for a park open only to white people. When the city stopped enforcing that restriction, a state court swapped in private trustees. After this ruling, Georgia courts sent the land back to Bacon’s heirs instead, which the Supreme Court allowed in Evans v. Abney (1970).

U.S. Supreme CourtJanuary 17, 1966382 U.S. 296

Read the opinion^[38]See alsoMarsh v. Alabama

Can an employer be blamed when a drunk worker causes damage nobody ordered? (Ira S. Bushey & Sons v. United States, 1968)

Ira S. Bushey & Sons v. United States1968Still cited

Yes, here. The government had to pay after a drunk Coast Guard sailor flooded a drydock, because that kind of risk comes with running a ship, even though no one ordered him to do it.

What it means for you. If someone’s employee harms you in a way that comes with the job, you can usually sue the business, not just the worker.

Second Circuit: Judge Henry Friendly wrote it.

The Coast Guard ship Tamaroa was being overhauled in a floating drydock in Brooklyn’s Gowanus Canal when a sailor coming back from shore leave late at night turned wheels on the drydock wall and opened valves that controlled its flooding. The drydock’s owner sued the government. Judge Henry Friendly said the sailor’s conduct was the kind a business should expect from its crew, even though no one told him to do it.

Vicarious liabilityBeing responsible for someone else’s wrong, like an employer for an employee’s, because of your relationship to them.

U.S. Court of Appeals for the Second Circuit1968398 F.2d 167

Find the decision^[39]See alsoCubby v. CompuServe Zeran v. AOL

Can the government make a newspaper print a candidate’s reply to criticism? (Miami Herald v. Tornillo, 1974)

Miami Herald v. Tornillo1974Still the law

No. Deciding what goes in the paper is editorial judgment the First Amendment protects, and a law forcing space for a reply intrudes on it, even when the paper attacked the candidate.

What it means for you. The government can’t tell a newspaper what to print, and in 2024 the Court said the same goes for how platforms arrange your feed.

Supreme Court, 9–0: Burger wrote it for all nine. Brennan and White added concurrences.

Pat Tornillo, a teachers’ union leader running for the Florida House, demanded space to answer the Herald’s editorials against him under a state right-of-reply law. Broadcasting was treated differently: in Red Lion (1969) the Court had upheld the fairness doctrine because the airwaves were scarce.

U.S. Supreme CourtJune 25, 1974418 U.S. 2419–0

Read the opinion^[40]See alsoMarsh v. Alabama Murthy v. Missouri

Is an online service liable for defamation in a newsletter it carries but never reads? (Cubby, Inc. v. CompuServe Inc., 1991)

Cubby, Inc. v. CompuServe Inc.1991Overtaken by Section 230

No. CompuServe was like a bookstore or a library, a distributor, and it could be liable only if it knew or should have known about the statements, which it didn’t.

One federal judge: Judge Peter Leisure decided it.

CompuServe’s Journalism Forum carried Rumorville USA, a daily newsletter about broadcast journalism published by an outside company. A competitor said Rumorville had defamed it and sued CompuServe too. CompuServe didn’t review the newsletter before it went up, Judge Peter Leisure found, so it couldn’t be treated as the publisher.

DistributorSomeone who passes along other people’s material, like a bookstore. A distributor is liable only if it knew or should have known the material was unlawful.

U.S. District Court, Southern District of New York1991776 F. Supp. 135

Find the decision^[41]See alsoStratton Oakmont v. Prodigy Zeran v. AOL

Is an online service liable for a user’s post because it moderates its message boards? (Stratton Oakmont v. Prodigy Services, 1995)

Stratton Oakmont v. Prodigy Services1995Overruled by Congress in 1996

Yes, said this New York court. Prodigy screened posts and promised a family-friendly service, so it was treated as the publisher of what users wrote, liable like a newspaper.

What it means for you. It’s why the sites you use can delete spam and abuse without becoming legally responsible for everything else you post.

One state trial judge: Justice Stuart Ain decided it. In New York, the trial court is called the Supreme Court.
Congress, 1996: The House added Section 230 to the bill 420–4. The whole Telecommunications Act passed 414–16 in the House and 91–5 in the Senate.

In October 1994, an anonymous user on Prodigy’s Money Talk board accused the securities firm Stratton Oakmont and its president, Daniel Porush, of criminal and fraudulent acts. Prodigy used content guidelines, screening software and board leaders it contracted with. Justice Stuart Ain said that control made it a publisher, unlike CompuServe in Cubby.

PublisherSomeone who chooses and edits what gets printed, and so can be sued over it like the author.

New York Supreme Court, a trial courtMay 24, 19951995 WL 323710

Find the decision^[42]See alsoCubby v. CompuServe Zeran v. AOL

Can a platform be sued for leaving up defamatory posts after it’s told about them? (Zeran v. America Online, 1997)

Zeran v. America Online1997Still followed

No. Section 230 bars treating a platform as the publisher of what users post, and the court read that to cover a platform that was warned about the posts and left them up.

What it means for you. Most courts follow it: you usually can’t sue a site for leaving up a false post about you, even after complaining. Justice Thomas has questioned that.

Fourth Circuit: Chief Judge Harvie Wilkinson wrote it.

An anonymous AOL user posted ads for T-shirts mocking the Oklahoma City bombing with Kenneth Zeran’s phone number, and he got angry calls and threats. Section 230 grew out of two earlier cases: CompuServe escaped liability because it didn’t moderate, and Prodigy was held liable because it did. Congress wanted to protect moderators. A limit came in Fair Housing Council v. Roommates.com (2008): a site that helps develop illegal content isn’t covered.

Section 230“No provider or user of an interactive computer service shall be treated as the publisher or speaker” of what someone else posted. It doesn’t cover federal crimes or copyright.

U.S. Court of Appeals for the Fourth CircuitNovember 12, 1997129 F.3d 327

Find the opinion^[43]See alsoTwitter v. Taamneh Reno v. ACLU Cubby Stratton Oakmont

Is a platform immune even when it pays the writer and promotes the post? (Blumenthal v. Drudge, 1998)

Blumenthal v. Drudge1998Still followed

Yes, under Section 230. AOL paid Matt Drudge and advertised his column, but because Drudge wrote it, not AOL, AOL couldn’t be sued over it. Blumenthal could still sue Drudge himself.

What it means for you. If a site pays someone to write a false story about you and promotes it, you can usually sue only the writer, not the site.

One federal judge: Judge Paul Friedman decided it.

Drudge reported, falsely, that White House aide Sidney Blumenthal had a history of abusing his wife, and retracted it the next day. Blumenthal could still sue Drudge himself, and dropped that suit in 2001.

U.S. District Court for the District of ColumbiaApril 22, 1998992 F. Supp. 44

Find the opinion^[44]See alsoZeran v. AOL

Can a company sue Google for pushing its site down in search results? (Search King v. Google Technology, 2003)

Search King v. Google Technology2003Still cited

Not here. PageRank is Google’s opinion about which sites matter, protected by the First Amendment, so lowering a site’s rank can’t be the basis for a lawsuit.

What it means for you. If Google buries your site or business in its results, you usually can’t sue: the ranking counts as Google’s opinion.

One federal judge: Judge Vicki Miles-LaGrange decided it.

Search King sold ads on sites with high PageRank scores and said Google deliberately cut its scores once it started competing with Google. The court treated the rankings as subjective, so they couldn’t be proven false.

U.S. District Court, Western District of OklahomaMay 27, 2003No. CIV-02-1457-M

Find the decision^[45]See alsoMiami Herald v. Tornillo Zeran v. AOL

Is Craigslist liable for discriminatory housing ads its users post? (Chicago Lawyers’ Committee v. Craigslist, 2008)

Chicago Lawyers’ Committee v. Craigslist2008Still the law in the Seventh Circuit

No. Section 230 keeps Craigslist from being treated as the speaker, and running a site anyone can post to doesn’t cause the ads. The people who wrote them can still be sued.

What it means for you. If you see a housing ad that says “no kids” or worse, you can file a fair-housing complaint against whoever posted it. The site itself is usually off the hook.

Seventh Circuit: Chief Judge Frank Easterbrook wrote it.

Users posted ads saying things like “no minorities” and “no children,” which the Fair Housing Act forbids. Judge Easterbrook suggested the Lawyers’ Committee use the ads to find and sue the people who posted them.

U.S. Court of Appeals for the Seventh CircuitMarch 14, 2008519 F.3d 666

Find the opinion^[46]See alsoRoommates.com Zeran v. AOL

Does Section 230 protect a site that asks users questions the law forbids? (Fair Housing Council v. Roommates.com, 2008)

Fair Housing Council v. Roommates.com2008Still the law in the Ninth Circuit

No. By requiring users to state their sex, sexual orientation and whether they had children, and letting others filter by the answers, the site helped develop the content, so it wasn’t immune for that part.

What it means for you. A site that forces you to answer illegal questions can be sued over them, even though it’s protected for what you write freely.

Ninth Circuit, full court: Chief Judge Alex Kozinski wrote for the majority after the whole court reheard the case.

Fair housing groups said the questions violated the Fair Housing Act. In a twist, the Ninth Circuit decided in 2012 that the Act doesn’t apply to choosing a roommate at all.

Information content providerAnyone responsible, in whole or in part, for creating or developing content. Section 230 doesn’t cover them for that content.

U.S. Court of Appeals for the Ninth Circuit, en bancApril 3, 2008521 F.3d 1157

Find the opinion^[47]See alsoZeran v. AOL

Is eBay liable for counterfeit Tiffany jewelry its sellers list? (Tiffany (NJ) Inc. v. eBay Inc., 2010)

Tiffany (NJ) Inc. v. eBay Inc.2010Still the law in the Second Circuit

No. Knowing in general that fakes get sold wasn’t enough; eBay had to know about specific listings, and it removed those when Tiffany reported them.

What it means for you. When you buy on a big online marketplace, it doesn’t have to screen every listing for fakes, only act on specific reports.

Second Circuit: Judge Robert Sack wrote it.

Tiffany sued after finding counterfeit Tiffany jewelry for sale on eBay. eBay ran its own reviews and a notice-and-takedown program called VeRO, and removed the listings rights owners reported. Judge Robert Sack wrote that a marketplace has to know about particular infringing listings before it’s liable for its sellers.

Notice and takedownA system where rights owners report specific listings or posts, and the platform removes them.

U.S. Court of Appeals for the Second Circuit2010600 F.3d 93

Find the decision^[48]See alsoViacom v. YouTube Zeran v. AOL

Does Section 230 protect an app from claims that its own feature is dangerous? (Lemmon v. Snap, Inc., 2021)

Lemmon v. Snap, Inc.2021Still the law in the Ninth Circuit

No. The parents’ claim was about Snapchat’s Speed Filter itself, a feature Snap designed, not anything a user posted, so Section 230 didn’t block it.

What it means for you. If an app’s own feature gets you hurt, you can sue the company over its design, even though it’s protected for what other users post.

In 2017, three young men died when their car hit a tree in Wisconsin at more than 100 miles per hour, minutes after one of them opened Snapchat’s Speed Filter, which showed how fast a user was going. Two of their parents sued Snap for negligent design, saying the feature encouraged young drivers to speed.

Design defectA claim that a product is dangerous because of how it was built, not because of how someone used it.

U.S. Court of Appeals for the Ninth Circuit2021995 F.3d 1085

Find the decision^[49]See alsoAnderson v. TikTok Roommates.com

Can platforms be sued over a terrorist attack because ISIS used their services? (Twitter, Inc. v. Taamneh, 2023)

Twitter, Inc. v. Taamneh2023Still the law

Not under the Anti-Terrorism Act, at least not like this. Running a service open to everyone, recommendations included, isn’t knowingly giving substantial help to a specific attack.

What it means for you. If you’re hurt in a terror attack, suing the platforms the attackers used will usually fail unless a platform knowingly helped that attack.

Supreme Court, 9–0: Thomas wrote it for all nine. Jackson added a concurrence.
Congress, 2016: The claim came from JASTA, which Congress passed over President Obama’s veto: Senate 97–1, House 348–77.

The family of Nawras Alassaf, killed in the 2017 attack on the Reina nightclub in Istanbul, sued Twitter, Google and Facebook for aiding and abetting ISIS. Justice Thomas wrote for a unanimous Court, working from Halberstam v. Welch (1983), the aiding-and-abetting case Congress named in the 2016 law that lets terrorism victims sue.

Section 230The 1996 law that mostly keeps platforms from being treated as the publisher of what their users post.

U.S. Supreme CourtMay 18, 2023598 U.S. 4719–0

Read it on the Court’s docket^[50]See alsoMurthy v. Missouri Anderson v. TikTok

Did federal officials violate the First Amendment by pressuring platforms to take down posts about COVID-19 and elections? (Murthy v. Missouri, 2024)

Murthy v. Missouri2024Question left open

Nobody knows yet. The Court didn’t decide, because the states and users who sued didn’t have standing: they couldn’t tie their own removed posts closely enough to anything the government did.

What it means for you. If officials pressure a platform into deleting your posts, the rules are still mostly unsettled. What’s clear, from NRA v. Vullo, is that they can’t threaten a company over your speech.

Supreme Court, 6–3: Majority: Barrett (wrote it), Roberts, Sotomayor, Kagan, Kavanaugh, Jackson.
Dissent: Alito, Thomas, Gorsuch.

Several friend-of-the-court briefs asked the Court to use the test from Bantam Books v. Sullivan (1963): officials can try to persuade a platform, but they can’t threaten or coerce it. Justice Barrett wrote for the majority. Justice Alito, joined by Justices Thomas and Gorsuch, dissented and called it one of the most important free-speech cases to reach the Court in years.

StandingTo sue, you have to show the other side caused you a specific injury that a court can fix.

U.S. Supreme CourtJune 26, 2024603 U.S. 436–3

Read it on the Court’s docket^[51]See alsoTwitter v. Taamneh

Does Section 230 protect TikTok when its algorithm pushes a deadly challenge to a 10-year-old? (Anderson v. TikTok, Inc., 2024)

Anderson v. TikTok, Inc.2024Sent back to the trial court

Not for the recommendation itself. Choosing what to put on someone’s For You page is TikTok’s own speech, and Section 230 only covers other people’s content, so the mother’s suit could go forward.

What it means for you. The Third Circuit covers Pennsylvania, so here, what an algorithm chooses to show you may fall outside Section 230. Other appeals courts had gone the other way.

Third Circuit: Judge Patty Shwartz wrote it, joined by Judge Peter Phipps; Judge Paul Matey agreed in part and wrote separately. The full court refused to rehear it.

Nylah Anderson died in December 2021 after trying the “Blackout Challenge,” a choking dare that TikTok’s algorithm had put on her For You page. A federal judge in Philadelphia threw out her mother’s suit under Section 230. Judge Patty Shwartz wrote for the Third Circuit, leaning on Moody v. NetChoice. The full court refused to rehear the case in October 2024, and TikTok said it would ask the Supreme Court to step in.

First-party speechA company’s own expression, as opposed to what its users post. Section 230 covers only the second.

U.S. Court of Appeals for the Third CircuitAugust 2024No. 22-3061

Find the decision^[52]See alsoTwitter v. Taamneh Lemmon v. Snap Miami Herald v. Tornillo

Can the FCC require internet providers to treat all traffic equally? (Ohio Telecom Association v. FCC, 2025)

Ohio Telecom Association v. FCC2025Rules struck down

Not under current law, the court held. Broadband is an information service, not a telecommunications service, so the FCC can’t impose rules built for phone companies. Congress could still pass them.

What it means for you. Without federal rules, your state decides whether your provider can slow some sites or sell a fast lane. California and others have their own rules.

The FCC: Voted 3–2 along party lines every time: to adopt the rules in 2015, repeal them in 2017, and restore them in 2024.
Congress: In 2018 the Senate voted 52–47 to undo the repeal; the House never voted on it.

The rules have flipped with each administration: adopted in 2015 and upheld in 2016, repealed in 2017, restored in 2024. Courts used to defer to the FCC’s reading of the law, but the Supreme Court ended that deference in 2024, and the Sixth Circuit read the statute for itself.

Title IIThe part of the Communications Act for common carriers like phone companies, which have to serve everyone on equal terms.

U.S. Court of Appeals for the Sixth CircuitJanuary 2, 2025No. 24-7000

Find the opinion^[53]See alsoWho controls a website

Next: Whose law applies

Whose law applies

A website opens anywhere. These cases decide which country’s rules, and which state’s courts, it has to answer to.

Can you be sued in a state you’ve never been to, over something you wrote about someone there? (Calder v. Jones, 1984)

Calder v. Jones1984Still the law

Yes, if you aimed it there. The Court let actress Shirley Jones sue National Enquirer staff in California because they targeted a Californian and the harm landed there.

What it means for you. Write about someone and you can be sued where they live and were hurt. Online, Young adds that you must have aimed at readers there.

Supreme Court, 9–0: Rehnquist wrote it for all nine.

The reporter and editor worked in Florida, but the story was about a California resident’s career and drew on California sources. The same day, in Keeton v. Hustler, the Court allowed a libel suit in New Hampshire because the magazine regularly sold copies there.

Effects testA court can hear a case against you where you aimed your conduct and the harm was felt.

U.S. Supreme CourtMarch 20, 1984465 U.S. 7839–0

Read the opinion^[54]See alsoYoung v. New Haven Advocate Zippo

When does running a website mean you can be sued in Pennsylvania? (Zippo Manufacturing v. Zippo Dot Com, 1997)

Zippo Manufacturing v. Zippo Dot Com1997Still cited, less used

It depends on what the site does. The court put websites on a sliding scale, from passive pages that only post information to sites that do business with a state’s residents, which can be sued there.

What it means for you. If you run an online shop, selling into another state can mean defending a lawsuit there. The more you target a state, the more exposed you are.

The lighter maker sued a California news service using the zippo.com domain. Zippo Dot Com had about 3,000 Pennsylvania subscribers and deals with seven Pennsylvania internet providers, which put it at the active end of the scale.

U.S. District Court, Western District of PennsylvaniaJanuary 16, 1997952 F. Supp. 1119

Find the opinion^[55]See alsoCalder v. Jones Young v. New Haven Advocate

What happens when someone registers a domain name that matches your name or brand? (ICANN’s domain-name dispute rules, 1999)

ICANN’s domain-name dispute rules1999In force

Usually a quick private arbitration. To win, a trademark owner has to show the name is confusingly similar to its mark, the holder has no legitimate interest in it, and it was registered and used in bad faith.

What it means for you. Every registrar makes you agree to these rules when you buy a domain, so a private contract, not a court, settles most domain fights worldwide.

ICANN: Adopted by ICANN’s board in 1999. Each dispute goes to a panel of one or three experts.

Panels can only transfer or cancel a name, not award money, and either side can still go to court. Courts have their own reach too: in GlobalSantaFe v. globalsantafe.com (2003), a Virginia judge took control of a name registered in Korea less than a day after a merger was announced, through the registry company based in Virginia.

Bad faithFor example, registering a name to sell it back to the trademark owner, or to pull in its customers.

ICANN, Uniform Domain-Name Dispute-Resolution PolicyAdopted October 24, 1999

How WIPO handles domain disputes^[56]See alsouBid v. GoDaddy

Can a French court make an American website block French users from Nazi memorabilia auctions? (Yahoo! v. La Ligue Contre le Racisme, 2001)

Yahoo! v. La Ligue Contre le Racisme2001Thrown out on appeal

Not in the U.S., said a federal judge. Enforcing it here would violate the First Amendment. In 2006 the full Ninth Circuit threw that ruling out without reaching the free-speech question, so there’s still no clean answer.

What it means for you. What you can legally post here can be illegal somewhere else, and courts still haven’t settled whether those countries can reach you.

One federal judge: Judge Jeremy Fogel ruled in 2001. The full Ninth Circuit threw his ruling out in 2006.

A Paris court ordered Yahoo! in 2000 to keep French users away from auctions of Nazi objects, which French law bans. Yahoo! asked a California federal court to declare the order unenforceable in the U.S. By then it had already pulled the auctions on its own.

EnforcementA foreign court’s order only has force in the U.S. if an American court agrees to back it.

U.S. District Court, Northern District of CaliforniaNovember 7, 2001169 F. Supp. 2d 1181

Find the decision^[57]See alsoOfcom Google v. CNIL

Can a businessman in Australia sue an American publisher over an article on its U.S. website? (Dow Jones & Co. v. Gutnick, 2002)

Dow Jones & Co. v. Gutnick2002Still the law in Australia

Yes. Australia’s highest court said an online article is published where it’s downloaded and read, so Joseph Gutnick could sue in Victoria, where he lived.

What it means for you. A post you write here can be sued over in Australia if people there read it. U.S. courts, as in Young, ask whose readers you were aiming at.

High Court of Australia, 7–0: All seven justices rejected Dow Jones’s appeal: Gleeson, McHugh, Gummow and Hayne in a joint judgment, with Gaudron, Kirby and Callinan writing separately.

Barron’s Online ran an article called “Unholy Gains” in October 2000 that mentioned Gutnick. Dow Jones argued the article was published in New Jersey, where its servers were. The parties later settled.

High Court of AustraliaDecember 10, 2002210 C.L.R. 575

Read the decision^[58]See alsoYoung v. New Haven Advocate Calder v. Jones

Can a Virginia prison warden sue Connecticut newspapers in Virginia over stories posted online? (Young v. New Haven Advocate, 2002)

Young v. New Haven Advocate2002Still the law in the Fourth Circuit

No. Posting stories that people in Virginia can read isn’t enough; the papers didn’t aim them at a Virginia audience, so Virginia courts couldn’t hear the case.

What it means for you. Where you can be sued for something you post depends on who you were writing for, not just who can see it.

Fourth Circuit: Judge Blane Michael wrote it.

Warden Stanley Young ran Wallens Ridge, a Virginia prison that took in prisoners from Connecticut. The New Haven Advocate and the Hartford Courant wrote critically about it, and Young sued for libel at home. A federal judge in Virginia let the case go ahead in 2001; the Fourth Circuit reversed.

Personal jurisdictionWhether a court in a given state has the power to hear a case against you at all.

U.S. Court of Appeals for the Fourth CircuitDecember 13, 2002315 F.3d 256

Find the decision^[59]See alsoYahoo! v. LICRA Dow Jones v. Gutnick

Does disability law cover a store’s website? (National Federation of the Blind v. Target, 2006)

National Federation of the Blind v. Target2006Settled in 2008

In part. Claims could go forward where the inaccessible site kept blind customers from using Target’s stores, like finding locations or store discounts, but not where the site had no connection to a store.

What it means for you. A site that doesn’t work with screen readers locks blind people out. Target paid $6 million and agreed to fix its site; online-only businesses are still contested.

One federal judge: Judge Marilyn Hall Patel decided it.

Target.com lacked basic alt text for images and couldn’t be used without a mouse, so blind shoppers using screen readers couldn’t buy anything. The court also rejected Target’s argument that applying California law to a national website would unconstitutionally regulate commerce in other states.

U.S. District Court, Northern District of CaliforniaSeptember 6, 2006452 F. Supp. 2d 946

Read the opinion^[60]See alsoZippo

Can a company that exists mostly online be sued in a state where it has no office? (uBid v. GoDaddy, 2010)

uBid v. GoDaddy2010Still the law in the Seventh Circuit

Yes, if it worked that state’s market. GoDaddy, based in Arizona, had deliberately and successfully exploited the Illinois market with national ads and Illinois customers, so uBid could sue it in Illinois.

What it means for you. An online company that advertises to you and takes your business can be sued in your state, even with no office there.

Seventh Circuit: Judge David Hamilton wrote it.

uBid, a Chicago online auction company, accused GoDaddy of cybersquatting on domain names that resembled its own. A trial court dismissed the case because GoDaddy kept its servers and staff in Arizona. The Seventh Circuit reversed, pointing to years of national TV ads, including six straight Super Bowls, much as Keeton v. Hustler had for a national magazine.

CybersquattingRegistering or using a domain name that matches someone else’s trademark, to profit from the confusion.

U.S. Court of Appeals for the Seventh Circuit2010623 F.3d 421

Read the opinion^[61]See alsoCalder v. Jones Zippo

When Google delists a result for someone in Europe, does it have to delist it everywhere in the world? (Google v. CNIL, 2019)

Google v. CNIL2019Still the law in the EU

No. EU law requires delisting on the versions for every EU country, not worldwide, plus steps to stop Europeans from switching versions. The court added that EU law doesn’t forbid a wider order either.

What it means for you. A result Google removes for someone in Europe can still show up when you search from the U.S.

EU Court of Justice: The Grand Chamber ruled. The court issues one judgment and never publishes votes or dissents.

France’s regulator, the CNIL, fined Google €100,000 in 2016 for limiting delisting to European versions of its search engine. Google appealed to the Conseil d’État, which asked the EU’s top court to settle it.

Court of Justice of the European UnionSeptember 24, 2019Case C-507/17

Read the judgment^[62]See alsoGoogle Spain Yahoo! v. LICRA

Can two American forums use a U.S. court to stop Britain’s online safety regulator from enforcing UK law against them? (4chan and Kiwi Farms v. Ofcom, 2026)

4chan and Kiwi Farms v. Ofcom2026Dismissed

No. Judge Rudolph Contreras dismissed the suit because Ofcom, as part of a foreign government, has sovereign immunity. He didn’t decide whether its demands violate the First Amendment.

What it means for you. Foreign online-safety laws can reach American sites you use. Whether they can be enforced here waits for an American court.

One federal judge: Judge Rudolph Contreras decided it.

Ofcom told 4chan in August 2025 that it planned to fine it £20,000, plus £100 a day, for not answering information requests under the act. The forums sued that month. Ofcom has since fined 4chan £520,000 over age checks and other requirements.

Sovereign immunityForeign governments generally can’t be sued in U.S. courts, apart from narrow exceptions.

U.S. District Court for the District of ColumbiaFiled August 27, 2025Dismissed September 15, 2026

Read the complaintSee alsoYahoo! v. LICRA Age verification

Next: Your data in Europe

Your data in Europe

In the EU, personal data is a right. These decisions shaped what that means for search engines and ad tracking.

Does a search engine have to stop linking to old news about you if you ask? (Google Spain v. AEPD and Costeja, 2014)

Google Spain v. AEPD and Costeja2014Still the law in the EU

It can. Google is responsible for the personal data in its results, and people can ask it to delist results that are inadequate, irrelevant or no longer relevant, weighed against the public’s interest in finding them.

What it means for you. In Europe you can ask Google to drop old, irrelevant results for your name, now a GDPR right. The U.S. has none, largely because of the First Amendment.

EU Court of Justice: The Grand Chamber ruled. The court issues one judgment and never publishes votes or dissents.

Mario Costeja González wanted Google to stop showing a 1998 newspaper notice about the auction of his property over social security debts he had long since paid. Spain’s data protection agency wouldn’t make the newspaper take it down, but told Google to stop linking to it.

DelistingRemoving a link from the results for a person’s name. The page itself stays online.

Court of Justice of the European UnionMay 13, 2014Case C-131/12

Read the judgment^[63]See alsoGoogle v. CNIL CNIL v. Google

Did Google get real consent before personalizing ads for Android users? (CNIL’s €50 million fine against Google, 2019)

CNIL’s €50 million fine against Google2019Upheld in 2020

No. Key information was spread across several pages and ad personalization was switched on by default, so the consent wasn’t specific or informed. The CNIL fined Google €50 million.

What it means for you. In Europe, a pre-checked box doesn’t count as your consent to ad tracking. There’s no general federal rule like that in the U.S.

CNIL: Issued by the CNIL’s sanctions panel. France’s highest administrative court upheld it in 2020.

Complaints from noyb and La Quadrature du Net arrived days after the GDPR took effect in May 2018. Google appealed, and France’s highest administrative court upheld the fine in June 2020.

Consent under the GDPRIt has to be freely given, specific, informed and unambiguous. A pre-checked box doesn’t count.

CNIL, France’s data protection authorityJanuary 21, 2019Decision SAN-2019-001

Read the decision (French)See alsoGoogle Spain

Next: Who controls a website

Who controls a website

Old property and contract rules, stretched to cover bots, email and the terms you click through.

Can a website stop another company’s bots from copying its listings? (eBay v. Bidder’s Edge, 2000)

eBay v. Bidder’s Edge2000Settled in 2001

Here, yes. The court ordered Bidder’s Edge to stop crawling eBay, calling it trespass to chattels, even though the bots never crashed anything.

What it means for you. The price trackers and research tools you use depend on scraping. This case let a site treat those bots as trespassers, until Intel v. Hamidi narrowed it.

One federal judge: Judge Ronald Whyte decided it.

Bidder’s Edge ran an auction search site that sent around 100,000 automated queries to eBay a day. The court found the crawling used only a small share of eBay’s capacity, but reasoned that allowing it would invite everyone else to do the same. It built on two earlier cases that treated electronic signals as physical contact: Thrifty-Tel v. Bezenek (1996), about break-ins to a phone company’s system, and CompuServe v. Cyber Promotions (1997), about spam.

Trespass to chattelsInterfering with someone else’s personal property without permission. Here the court treated eBay’s servers as the property.

U.S. District Court, Northern District of CaliforniaMay 24, 2000100 F. Supp. 2d 1058

Read the opinion^[64]See alsoIntel v. Hamidi The law of the horse

Are you bound by terms you could only find by scrolling past the download button? (Specht v. Netscape Communications, 2002)

Specht v. Netscape Communications2002Still the law in the Second Circuit

No. Downloading software isn’t agreeing to its license when the terms sit below the screen with no reasonable notice, so users didn’t have to go to arbitration.

What it means for you. Terms bind you only if you could see them and did something showing you agreed. A link beside the sign-up button has been enough, as in Fteja v. Facebook (2012).

Second Circuit: Then-Judge Sonia Sotomayor wrote it.

Netscape offered free SmartDownload software whose license, with an arbitration clause, appeared only if users scrolled down past the download button. Then-Judge Sonia Sotomayor wrote the opinion. It contrasts with ProCD v. Zeidenberg (1996), which enforced a license packed inside a software box because buyers could read it and return the product.

Clickwrap and browsewrapClickwrap makes you click “I agree.” Browsewrap just links the terms somewhere on the page.

U.S. Court of Appeals for the Second CircuitOctober 1, 2002306 F.3d 17

Find the opinion^[65]See alsoeBay v. Bidder’s Edge CNIL’s fine against Google Hancock v. AT&T

Was a former employee trespassing when he emailed tens of thousands of Intel workers through Intel’s own network? (Intel Corp. v. Hamidi, 2003)

Intel Corp. v. Hamidi2003Still the law in California

No. Trespass to chattels requires harm to the system, and his emails didn’t slow or impair Intel’s computers. Intel’s real objection was what they said.

What it means for you. A company can’t sue you for trespass just for emailing its employees, unless your messages actually harm its system.

California Supreme Court, 4–3: Justice Kathryn Werdegar wrote for the majority. Three justices dissented.

Ken Hamidi, fired by Intel in 1995, sent six mass emails over 21 months to as many as 35,000 employees and removed anyone who asked. The trial court and the Court of Appeal both sided with Intel. The California Supreme Court reversed.

Supreme Court of CaliforniaJune 30, 200330 Cal. 4th 13424–3

Read the opinion^[66]See alsoeBay v. Bidder’s Edge

Can a site’s terms bind a company whose robot never clicked “I agree”? (Register.com v. Verio, 2004)

Yes, if it keeps coming back knowing the terms. Verio queried Register.com’s database over and over, saw the terms each time, and accepted them by continuing.

What it means for you. If you run a scraper or bot against a site, its terms can bind you just because you keep coming back after seeing them.

Second Circuit: Judge Pierre Leval wrote it.

Register.com let anyone look up who owned a domain, with terms banning use of the results for mass marketing. Verio’s robot pulled the contact details of new domain owners to pitch them by email, phone and mail. The court also upheld an order against the robot itself under trespass to chattels.

U.S. Court of Appeals for the Second CircuitJanuary 23, 2004356 F.3d 393

Find the opinion^[67]See alsoSpecht v. Netscape eBay v. Bidder’s Edge

Can a game company force players into arbitration with terms they can’t negotiate? (Bragg v. Linden Research, 2007)

Bragg v. Linden Research2007Settled in 2007

Not on these terms. The court refused to enforce Second Life’s arbitration clause because it was unconscionable: take-it-or-leave-it, costly, set in San Francisco, and one-sided.

What it means for you. Clicking “I agree” doesn’t make every term enforceable. Decided in Philadelphia, it was one of the first cases to treat a fight over virtual property as a real one.

One federal judge: Judge Eduardo Robreno decided it, in Philadelphia.

Marc Bragg, a Pennsylvania lawyer, bought virtual land through a loophole in Second Life’s auctions. Linden Lab froze his account, took his land and in-game money, and pointed to its terms to send the fight to arbitration. The case settled later that year.

UnconscionableSo one-sided and unfair that a court won’t enforce it, usually because one side had no real choice.

U.S. District Court, Eastern District of PennsylvaniaMay 30, 2007487 F. Supp. 2d 593

Find the opinion^[68]See alsoSpecht v. Netscape

Are you bound by terms you accepted with a click before your service would start? (Hancock v. American Telephone & Telegraph Co., 2012)

Hancock v. American Telephone & Telegraph Co.2012Still the law in the Tenth Circuit

Yes. AT&T’s U-verse customers clicked to accept the terms, and the court treated that as a valid clickwrap agreement, so their class action was dismissed.

What it means for you. Clicking “I agree” usually binds you, even if nobody reads the terms. Specht is the exception, for terms you never had a fair chance to see.

Tenth Circuit: Judge Scott Matheson wrote it.

U-verse bundled TV, phone and internet service. Customers who wanted to sue as a class argued, relying on Specht, that the click-through process gave them no real chance to agree. Judge Scott Matheson’s opinion for the court disagreed.

U.S. Court of Appeals for the Tenth Circuit2012701 F.3d 1248

Find the decision^[69]See alsoSpecht v. Netscape Register.com v. Verio

Next: Copyright online

Copyright online

What copyright protects: facts versus creative choices, who owns the news, tools that can copy, file sharing, copy protection, and the takedown system that decides what stays up online.

Can Congress protect brand names using its power over copyrights and patents? (The Trade-Mark Cases, 1879)

The Trade-Mark Cases1879Still the law

No. A trademark isn’t an invention or an original writing, so that power doesn’t reach it. Congress rewrote trademark law in 1881 under its power over commerce.

Supreme Court, unanimous: Justice Samuel Miller wrote it for the whole Court.

Congress passed the first federal trademark registration law in 1870. Three prosecutions for counterfeit marks, two over champagne and one over whiskey, reached the Court together, and the justices were unanimous.

Copyright ClauseThe part of the Constitution that lets Congress protect authors’ writings and inventors’ discoveries for limited times.

U.S. Supreme CourtNovember 17, 1879100 U.S. 82

Read the opinion^[70]See alsoFeist United States v. Moghadam

Can a news service copy a rival’s scoops and resell them while they’re still fresh? (International News Service v. Associated Press, 1918)

International News Service v. Associated Press1918Still cited

No. The news itself can’t be copyrighted, but the Court said taking a rival’s fresh reporting to sell as your own was unfair competition.

What it means for you. The facts in the news belong to everyone, so you can repeat them. Reselling someone’s reporting while it’s fresh is another matter.

Supreme Court, 5–3: Majority: Pitney (wrote it), White, Day, Van Devanter, McReynolds.
Dissent: Holmes and McKenna, who would only have required credit to the AP, and Brandeis. Clarke sat out.

During World War I, Britain and France cut William Randolph Hearst’s International News Service off their telegraph lines over coverage they saw as favoring Germany. INS kept covering the war by copying Associated Press bulletins and early editions and selling the stories, sometimes rewritten, to its own papers. Justice Pitney called news a kind of quasi-property between competitors.

Hot newsA narrow claim against copying a rival’s time-sensitive news while it’s still fresh, based on unfair competition rather than copyright.

U.S. Supreme Court1918248 U.S. 215

Read the opinion^[71]See alsoFeist

Is it illegal to sell a machine people can use to copy TV shows? (Sony Corp. of America v. Universal City Studios, 1984)

Sony Corp. of America v. Universal City Studios1984Still the law

No. The Betamax had substantial legal uses, above all taping a show to watch later, which the Court called fair use, so Sony wasn’t liable for buyers who copied.

What it means for you. It’s why you can buy a laptop, phone or DVR that can copy anything: the maker isn’t to blame for what some buyers do with it.

Supreme Court, 5–4: Majority: Stevens (wrote it), Burger, Brennan, White, O’Connor.
Dissent: Blackmun, Marshall, Powell, Rehnquist.

Universal and Disney sued Sony over its Betamax video recorders. Justice Stevens wrote for the majority; Justice Blackmun’s dissent would have held Sony responsible.

Substantial noninfringing useA real, significant legal use. A product that has one can be sold even if some buyers use it to infringe.

U.S. Supreme Court1984464 U.S. 4175–4

Read the opinion^[72]See alsoA&M Records v. Napster MGM v. Grokster

Can you copyright a phone book? (Feist Publications v. Rural Telephone Service, 1991)

Feist Publications v. Rural Telephone Service1991Still the law

Not its facts. Copyright protects original creative choices, not hard work, so the names and numbers in a white-pages listing are free for anyone to copy.

What it means for you. It’s why facts and raw data can’t be owned through copyright, a question that keeps coming back with databases, scraping and AI training sets.

Supreme Court, 9–0: O’Connor wrote it. Blackmun agreed with the result separately.

Rural Telephone refused to license its listings to Feist, which was building a regional directory, and Feist copied them anyway. Justice O’Connor rejected the “sweat of the brow” idea that effort alone earns protection; a compilation is protected only for an original selection or arrangement. Facts were already free: in Rosemont v. Random House (1966), Howard Hughes bought the copyrights to magazine articles about himself and still couldn’t stop a biography.

U.S. Supreme CourtMarch 27, 1991499 U.S. 3409–0

Read the opinion^[73]See alsoeBay v. Bidder’s Edge INS v. Associated Press

Is an internet provider an infringer when its servers automatically copy what a user posts? (Religious Technology Center v. Netcom, 1995)

Religious Technology Center v. Netcom1995Written into the DMCA in 1998

Not directly. Copies made automatically by a system that serves everyone aren’t the provider’s own infringement, though it could be liable if it knew about the posts and did nothing.

What it means for you. It’s why your internet provider and the sites you post on aren’t sued over every upload, as long as they act on takedown notices.

One federal judge: Judge Ronald Whyte decided it.

Dennis Erlich, a former Scientology minister turned critic, posted the church’s copyrighted writings to a Usenet discussion group. He got online through a small bulletin board run out of Thomas Klemesrud’s home, which connected through Netcom. Two church-affiliated groups sued all three, and Judge Ronald Whyte let the claim that Netcom contributed to the infringement go forward.

Safe harborA rule that protects a company from being sued if it follows certain steps. The DMCA’s safe harbors cover providers that act on takedown notices.

U.S. District Court, Northern District of California1995907 F. Supp. 1361

Find the decision^[74]See alsoViacom v. YouTube Lenz v. Universal

Can Congress make it a crime to sell bootleg recordings of live concerts when copyright can’t cover them? (United States v. Moghadam, 1999)

United States v. Moghadam1999Still the law in the Eleventh Circuit

Yes. The court assumed copyright’s power doesn’t reach performances nobody recorded, but upheld the law under Congress’s power over commerce.

What it means for you. Recording a concert without permission and selling it is a federal crime, even though copyright itself doesn’t cover a live show.

A 1994 law made it a crime to record live musical performances without permission, or to sell or traffic in those recordings. Charged with selling bootleg CDs, Moghadam argued the law fell outside every power the Constitution gives Congress, since a live show isn’t a fixed writing.

FixationCopyright’s requirement that a work be captured in some lasting form, like a recording or a page.

U.S. Court of Appeals for the Eleventh Circuit1999175 F.3d 1269

Find the decision^[75]See alsoTrade-Mark Cases Feist

Is a file-sharing service liable when its own servers list the songs people are trading? (A&M Records v. Napster, 2001)

A&M Records v. Napster2001Still the law in the Ninth Circuit

Yes. Napster’s central index showed it what was being traded and let it cut off users, so Sony’s Betamax rule didn’t save it.

What it means for you. Sharing music files you don’t have the rights to is infringement, and a service that indexes them can be held responsible too.

Ninth Circuit: Judge Robert Beezer wrote it.

Napster users listed the music files on their computers in a central directory on Napster’s servers, searched it, and downloaded from one another. Record companies sued. Judge Robert Beezer’s opinion found the users were infringing and Napster knew it.

Contributory and vicarious infringementLiability for someone else’s copying: contributory if you knowingly help, vicarious if you can control it and profit from it.

U.S. Court of Appeals for the Ninth Circuit2001239 F.3d 1004

Find the decision^[76]See alsoSony v. Universal MGM v. Grokster

Is computer code speech, and can a site be stopped from posting code that breaks DVD copy protection? (Universal City Studios v. Corley, 2001)

Universal City Studios v. Corley2001Still the law in the Second Circuit

Code is speech, but what it does can still be regulated. The court upheld an order against posting, or even linking to, DeCSS under the DMCA’s anti-circumvention rules.

What it means for you. Breaking copy protection can be illegal even for a legal purpose. This is the main case on that rule, the one behind right-to-repair fights.

Second Circuit: Judge Jon Newman wrote it.

Eric Corley, publisher of the hacker magazine 2600, posted DeCSS on 2600.com in 1999 along with links to other sites carrying it. The court said code’s functional side, its ability to make a computer act instantly, lets the government regulate it in ways it couldn’t regulate a recipe or a blueprint. A federal court applied the same rule to streaming in RealNetworks v. Streambox (2000), stopping software built to get around RealPlayer’s “Secret Handshake.”

Anti-circumventionThe DMCA’s ban on breaking copy protection, or trafficking in tools that do, even for a use that would otherwise be legal.

U.S. Court of Appeals for the Second CircuitNovember 28, 2001273 F.3d 429

Find the opinion^[77]See alsoLenz v. Universal

Is a company liable when people use its file-sharing software to pirate music and movies? (MGM Studios v. Grokster, 2005)

MGM Studios v. Grokster2005Still the law

It can be. A company that distributes software to promote infringement is liable for what its users do, even if the software has legal uses too.

What it means for you. The file-sharing apps you use are legal to make. The trouble starts when a company advertises one for piracy.

Supreme Court, 9–0: Souter wrote it for all nine. Ginsburg and Breyer wrote concurrences that split over how the Betamax rule applied.

In Sony v. Universal (1984), the Court held that selling VCRs wasn’t infringement because taping shows to watch later is a legitimate use. Napster lost in 2001 because its central servers let it see and stop the trading. Grokster had no central server, so the Court looked at intent: it courted former Napster users and made money from ads they saw while trading files.

InducementActively encouraging other people to infringe, for example by advertising a tool for it.

U.S. Supreme CourtJune 27, 2005545 U.S. 9139–0

Read the opinion^[78]See alsoLenz v. Universal Sony v. Universal Napster

Does YouTube lose its legal shield because it knew piracy was common on the site? (Viacom International v. YouTube, 2012)

Viacom International v. YouTube2012Settled after YouTube won again

No. General awareness isn’t enough. YouTube loses the DMCA’s safe harbor only for specific clips it knew, or obviously should have known, were infringing.

What it means for you. It’s why you can upload to YouTube without each video being checked first: platforms only have to act on what they know about specific videos.

Second Circuit: Judge José Cabranes wrote it.

Viacom and other rights holders sued over clips users had uploaded. The Second Circuit sent the case back to look at evidence that YouTube knew about particular videos. Judge Louis Stanton ruled for YouTube again in 2013, and the parties settled after an appeal. The Ninth Circuit reached a similar result for Veoh, a smaller video site, in UMG Recordings v. Shelter Capital Partners (2013).

Red flag knowledgeBeing aware of facts that make specific infringement obvious. Under the DMCA, it can cost a platform its safe harbor.

U.S. Court of Appeals for the Second Circuit2012676 F.3d 19

Find the decision^[79]See alsoRTC v. Netcom Lenz v. Universal Tiffany v. eBay

Is it legal to rent each subscriber a tiny antenna and stream broadcast TV to them online? (American Broadcasting Cos. v. Aereo, 2014)

American Broadcasting Cos. v. Aereo2014Still the law

No. Aereo was performing the shows publicly, much like a cable company, so it needed the broadcasters’ permission.

What it means for you. A cheaper TV service built on a technical loophole won’t last if it’s really cable without permission. Aereo shut down within days.

Supreme Court, 6–3: Majority: Breyer (wrote it), Roberts, Kennedy, Ginsburg, Sotomayor, Kagan.
Dissent: Scalia, Thomas, Alito.

Aereo kept thousands of dime-sized antennas in a warehouse and assigned one to each viewer. Justice Scalia dissented, calling the majority’s approach a looks-like-cable test. Aereo shut down within days and went bankrupt that fall.

U.S. Supreme CourtJune 25, 2014573 U.S. 4316–3

Read the opinion^[80]See alsoMGM v. Grokster

Do copyright holders have to think about fair use before sending a takedown notice? (Lenz v. Universal Music, 2016)

Lenz v. Universal Music2016Still the law in the Ninth Circuit

Yes. Before telling a platform to remove something, they have to consider whether it’s fair use, though an honest belief that it isn’t is enough.

What it means for you. If your video gets taken down, the claimant was supposed to consider fair use first, and you can push back with a counter-notice.

Stephanie Lenz posted a 29-second video of her toddler dancing to Prince’s “Let’s Go Crazy,” and Universal had YouTube take it down. Under the DMCA’s safe harbor, a platform that removes material quickly after notice can’t be sued over it, so platforms tend to comply without checking.

Counter-noticeYour formal reply to a takedown. The platform can restore the post after 10 to 14 business days unless the claimant sues.

U.S. Court of Appeals for the Ninth CircuitMarch 17, 2016815 F.3d 1145

Find the opinion^[81]See alsoMGM v. Grokster Viacom v. YouTube

Next: Ideas worth knowing

Ideas worth knowing

Arguments that explain why the law treats the internet the way it does.

Where does the legal idea of privacy come from? (The right to privacy, 1890)

The right to privacy1890An argument, not a ruling

From an 1890 article. Samuel Warren and Louis Brandeis called it the right to be let alone, and Alan Westin later defined it as people’s claim to decide when, how and how much information about them reaches others.

What it means for you. It’s the idea behind much of the privacy law that protects you, and it started as a complaint about cameras and gossip papers.

Brandeis carried the idea onto the Supreme Court. The briefs in Chatrie reach back further, to Entick v. Carrington (1765), an English case against officers who broke into a writer’s house to take his papers. His dissent in Olmstead (1928) warned that technology would let the government invade privacy without entering a home, and Katz adopted that view in 1967.

Samuel Warren and Louis Brandeis, 4 Harv. L. Rev. 193 (1890)Alan Westin, Privacy and Freedom (1967)

Can national governments regulate the internet at all? (Does the internet have borders?, 1996)

Does the internet have borders?1996An argument, not a ruling

Mostly, yes. In 1996, Barlow told governments they had no sovereignty in cyberspace, and Johnson and Post argued it needed its own rules. Jack Goldsmith answered that territorial law still works, because people, servers and companies are all somewhere.

What it means for you. Your government can reach the sites you use even when they’re based abroad, and other countries can reach sites based here.

Johnson and Post said rules tied to physical places lose their power, effects, legitimacy and notice online. Goldsmith replied that the same problems existed before the internet, and that governments can regulate local users, local equipment and companies with local assets.

John Perry Barlow, A Declaration of the Independence of Cyberspace (1996)David Johnson and David Post, 48 Stan. L. Rev. 1367 (1996)Jack Goldsmith, 65 U. Chi. L. Rev. 1199 (1998)

Read Barlow’s declaration^[82]See alsoYahoo! v. LICRA Google v. CNIL

Is there such a thing as cyberlaw, or just ordinary law applied to computers? (The law of the horse, 1999)

The law of the horse1999An argument, not a ruling

It depends who you ask. Judge Frank Easterbrook argued in 1996 that a course on cyberlaw makes as much sense as one on the law of the horse. Lawrence Lessig answered in 1999 that the internet teaches something new: code regulates too, alongside laws, social norms and markets.

What it means for you. It’s why this site covers settings and software as well as bills. How an app is built can protect your privacy or erase it, whatever the law says.

Easterbrook’s point was that studying horse sales and horse injuries separately would miss the general rules that tie the law together, and that computers are no different. Lessig’s reply was the idea behind his book Code: what software allows and forbids is a kind of regulation, and lawmakers can shape it.

Frank Easterbrook, 1996 U. Chi. Legal F. 207Lawrence Lessig, 113 Harv. L. Rev. 501 (1999)

Read Lessig’s article^[83]See alsoeBay v. Bidder’s Edge

Is hate speech protected by the First Amendment? (Hate speech and the First Amendment, 2003)

Hate speech and the First Amendment2003Mostly protected

Mostly, yes. There’s no hate-speech exception, but true threats, incitement and targeted harassment can still be punished, whatever the motive behind them.

What it means for you. It’s why state schools like Pitt can’t ban offensive speech outright, and why speech codes at schools like the University of Michigan have been struck down.

The narrow exceptions go back to Chaplinsky v. New Hampshire (1942), which allowed punishing fighting words, the kind likely to start a fight. In R.A.V. v. St. Paul (1992), the Court struck down a city ban on bias-motivated disorderly conduct because it singled out some viewpoints for punishment. In Virginia v. Black, the Court said a state can ban cross burning meant to intimidate, but can’t treat every cross burning as proof of that intent. In Skokie, Illinois courts let a Nazi group march in a town that was home to many Holocaust survivors. The Supreme Court refused again to create a hate-speech exception in Matal v. Tam (2017).

True threatA serious statement of intent to commit violence against a particular person or group. It isn’t protected.

Virginia v. Black, 538 U.S. 343 (2003)Village of Skokie v. National Socialist Party (Ill. 1978)

Read Virginia v. Black^[84]See alsoBrandenburg v. Ohio Counterman v. Colorado

Next: Words to know

Words to know

Every term the entries define, in one place, with a link to the entry it comes from.

Anti-circumvention: The DMCA’s ban on breaking copy protection, or trafficking in tools that do, even for a use that would otherwise be legal. From Universal v. Corley
Backdoor search: Querying data collected under Section 702 with an American’s name, email address or other identifier. From United States v. Hasbajrami
Bad faith: For example, registering a name to sell it back to the trademark owner, or to pull in its customers. From Domain-name disputes
Beeper: A small radio transmitter hidden in an object so police could follow its signal. GPS trackers have replaced them. From United States v. Knotts
Cell-site location records: The log of which towers your phone connected to, and when. Carriers keep it whether or not you use location services. From Carpenter v. United States
CIPA: The Children’s Internet Protection Act. Schools and libraries that take certain federal internet money have to filter their computers. From U.S. v. American Library Ass’n
Clickwrap and browsewrap: Clickwrap makes you click “I agree.” Browsewrap just links the terms somewhere on the page. From Specht v. Netscape
Consent under the GDPR: It has to be freely given, specific, informed and unambiguous. A pre-checked box doesn’t count. From CNIL’s fine against Google
Contributory and vicarious infringement: Liability for someone else’s copying: contributory if you knowingly help, vicarious if you can control it and profit from it. From A&M Records v. Napster
Copyright Clause: The part of the Constitution that lets Congress protect authors’ writings and inventors’ discoveries for limited times. From Trade-Mark Cases
Counter-notice: Your formal reply to a takedown. The platform can restore the post after 10 to 14 business days unless the claimant sues. From Lenz v. Universal
Curtilage: The area right around a home, like a porch or yard, that the law treats as part of the home itself. From Florida v. Jardines
Cybersquatting: Registering or using a domain name that matches someone else’s trademark, to profit from the confusion. From uBid v. GoDaddy
Delisting: Removing a link from the results for a person’s name. The page itself stays online. From Google Spain
Design defect: A claim that a product is dangerous because of how it was built, not because of how someone used it. From Lemmon v. Snap
Distributor: Someone who passes along other people’s material, like a bookstore. A distributor is liable only if it knew or should have known the material was unlawful. From Cubby v. CompuServe
Effects test: A court can hear a case against you where you aimed your conduct and the harm was felt. From Calder v. Jones
Enforcement: A foreign court’s order only has force in the U.S. if an American court agrees to back it. From Yahoo! v. LICRA
First-party speech: A company’s own expression, as opposed to what its users post. Section 230 covers only the second. From Anderson v. TikTok
FISA court: A special court of federal judges that approves surveillance orders in secret, usually hearing only from the government. From FISA
Fixation: Copyright’s requirement that a work be captured in some lasting form, like a recording or a page. From United States v. Moghadam
General public use: The Court’s caveat. The more common a technology gets, the weaker this protection may become. From Kyllo v. United States
Geofence warrant: A warrant for every device in an area during a time window, instead of for one named suspect. From Chatrie v. United States
Hot news: A narrow claim against copying a rival’s time-sensitive news while it’s still fresh, based on unfair competition rather than copyright. From INS v. Associated Press
Imminent lawless action: Speech aimed at producing lawbreaking right away, and likely to, rather than at some point in the future. From Brandenburg v. Ohio
Indecent and obscene: Obscene material has no First Amendment protection. Indecent material does, at least for adults. From Reno v. ACLU
Inducement: Actively encouraging other people to infringe, for example by advertising a tool for it. From MGM v. Grokster
Information content provider: Anyone responsible, in whole or in part, for creating or developing content. Section 230 doesn’t cover them for that content. From Roommates.com
Intermediate scrutiny: A middle test: the law has to serve an important interest without burdening much more speech than it needs to. From Free Speech Coalition v. Paxton
Keyword warrant: A warrant that names search terms instead of a suspect, and asks a company who searched for them. From Commonwealth v. Kurtz
Metadata: Who called whom, when, and for how long, but not what was said. From ACLU v. Clapper
Mosaic theory: The idea that many small observations, added together, can reveal a whole life even when no single one would. From United States v. Jones
Notice and takedown: A system where rights owners report specific listings or posts, and the platform removes them. From Tiffany v. eBay
Overblocking: When a filter or block cuts off lawful sites along with the ones it was aimed at. From CDT v. Pappert
Overbreadth: A law falls if it bans a substantial amount of protected speech along with what it’s allowed to ban. From Ashcroft v. Free Speech Coalition
Pen register: A device that logs the numbers dialed from a phone line, not what is said on the calls. From Smith v. Maryland
Personal jurisdiction: Whether a court in a given state has the power to hear a case against you at all. From Young v. New Haven Advocate
Publisher: Someone who chooses and edits what gets printed, and so can be sued over it like the author. From Stratton Oakmont v. Prodigy
Reasonable expectation of privacy: Justice Harlan’s two-part test: you actually expected privacy, and society is prepared to treat that expectation as reasonable. From Katz v. United States
Recklessness: Knowing there’s a real risk your words will be taken as a threat, and sending them anyway. From Counterman v. Colorado
Red flag knowledge: Being aware of facts that make specific infringement obvious. Under the DMCA, it can cost a platform its safe harbor. From Viacom v. YouTube
Retroactive immunity: A law passed after the fact that wipes out liability for what a company already did. From Hepting v. AT&T
Safe harbor: A rule that protects a company from being sued if it follows certain steps. The DMCA’s safe harbors cover providers that act on takedown notices. From RTC v. Netcom
Section 230: “No provider or user of an interactive computer service shall be treated as the publisher or speaker” of what someone else posted. It doesn’t cover federal crimes or copyright. From Zeran v. AOL
Section 241: An 1870 law that makes it a crime for two or more people to conspire to injure anyone’s exercise of a right, including voting. From United States v. Mackey
Section 702: It lets intelligence agencies collect foreigners’ communications without individual warrants. Americans’ messages get swept up too. From Clapper v. Amnesty
Sovereign immunity: Foreign governments generally can’t be sued in U.S. courts, apart from narrow exceptions. From 4chan and Kiwi Farms v. Ofcom
Standing: To sue, you have to show the other side caused you a specific injury that a court can fix. From Murthy v. Missouri
State action: The First Amendment limits the government, not private companies, unless a company is doing the government’s job or acting at its direction. From Marsh v. Alabama
Stored Communications Act: The 1986 law that sets the rules for police getting records and messages from email and internet companies. From United States v. Warshak
Subpoena: A court order to turn over information or testify. Here, an order telling an internet provider to name its customers. From Sony Music v. Does 1–40
Substantial noninfringing use: A real, significant legal use. A product that has one can be sold even if some buyers use it to infringe. From Sony v. Universal
Timeline: Google Maps’ record of where you’ve been, formerly Location History. Google says it now keeps it only on your device. From Chatrie v. United States
Title II: The part of the Communications Act for common carriers like phone companies, which have to serve everyone on equal terms. From Net neutrality
Trespass to chattels: Interfering with someone else’s personal property without permission. Here the court treated eBay’s servers as the property. From eBay v. Bidder’s Edge
True threat: A serious statement of intent to commit violence against a particular person or group. It isn’t protected. From Hate speech
Unconscionable: So one-sided and unfair that a court won’t enforce it, usually because one side had no real choice. From Bragg v. Linden Research
Unmasking: A court order making a website or internet provider reveal who is behind an anonymous account. From Doe v. Cahill
Vicarious liability: Being responsible for someone else’s wrong, like an employer for an employee’s, because of your relationship to them. From Bushey v. United States
Voter intimidation: Threatening or scaring people to keep them from voting. Section 11(b) of the Voting Rights Act bans it. From National Coalition v. Wohl
Wiretap order: A court order letting police listen to calls or conversations as they happen. Federal law requires more for one than for an ordinary search warrant. From Berger v. New York

Next: Bills and rules we track

Bills and rules we track

These get their full explanation on other pages of the site.

Surveillance Accountability ActH.R. 8470, in the House
Fourth Amendment Is Not For Sale ActPassed the House in 2024, died in the Senate
Section 702 of FISALapsed June 2026; renewal fight continues
Pennsylvania plate-reader billsAt least nine filed
Pennsylvania Consumer Data Privacy ActHB 78, awaiting a Senate vote
Pennsylvania Right-to-Know LawIn force; Pitt is largely exempt
Pitt’s 2019 camera policyIn force; never mentions plate readers
FERPAIn force; covers your student records

References84 sources

Every source this page cites, numbered in the order it first appears. Each number in the text links here; each ^ links back.

^ Berger v. New York (1967), opinion — Justia supreme.justia.com/cases/federal/us/388/41
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^ Smith v. Maryland (1979), opinion — Justia supreme.justia.com/cases/federal/us/442/735
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^ Kyllo v. United States (2001), opinion — Justia supreme.justia.com/cases/federal/us/533/27
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^ Riley v. California (2014), opinion — Justia supreme.justia.com/cases/federal/us/573/373
^ Carpenter v. United States (2018), opinion — Supreme Court of the United States supremecourt.gov/opinions/17pdf/16-402_h315.pdf
^ Commonwealth v. Kurtz (2025), opinion — CourtListener courtlistener.com
^ Schmidt v. City of Norfolk (2026), opinion — ACLU case page aclu.org/cases/schmidt-v-norfolk
^ Chatrie v. United States (2026), opinion — Supreme Court of the United States supremecourt.gov/opinions/25pdf/25-112_0am4.pdf
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^ Hepting v. AT&T (2006), opinion — CourtListener, Find the case courtlistener.com
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^ FCC v. Pacifica Foundation (1978), opinion — Justia supreme.justia.com/cases/federal/us/438/726
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