The case in one breath Federal agents had a judge’s permission to put a GPS tracker on a Washington, D.C. nightclub owner’s Jeep — and then missed both of its conditions. They attached the device a day late and in the wrong state, then logged the Jeep’s every move for 28 days. In 2012, all nine justices agreed that was a searchSearch: government action the Fourth Amendment covers. Once something counts as a search, it has to be reasonable — which usually, but not always, means a warrant. under the Fourth Amendment. What they could not agree on was why. Five said the answer was old and simple: the government stuck its hardware on a man’s property to collect information — a trespassTrespass: physically intruding on someone else’s property without permission. Jones revived it as a way to spot a Fourth Amendment search.. Four said the real problem was a month of nonstop tracking, no matter how it was done. Jones is the Supreme Court’s GPS case — and the unfinished argument inside it is the one that later reached your phone.
Decided
January 23, 2012
Vote
9–0
Opinion by
Justice Scalia
Protects
Your property from secret trackers
The Story Behind United States v. Jones
It started with a drug investigation, a nightclub, and a warrant that agents had in hand — and then didn’t follow.2004Antoine Jones owns and runs a nightclub in Washington, D.C. A joint FBI and D.C. police task force suspects him of trafficking drugs. Officers watch the club, aim a camera at its front door, and tap his cell phone.
THE WARRANTIn 2005 the government asks a federal court for a warrantWarrant: a judge’s written permission for a search. It comes with terms — where, when, what — and officers are supposed to stay inside them. to put a tracking device on a Jeep Grand Cherokee registered to Jones’s wife, which he alone drives. The court says yes, with two conditions: install it in the District of Columbia, and do it within 10 days.
DAY 11Agents miss both. On the 11th day, in Maryland, they attach a GPS device to the Jeep’s undercarriage in a public parking lot. For the next 28 days it reports the Jeep’s location to within 50 to 100 feet — more than 2,000 pages of data. Agents even come back once to replace the battery.
THE TRIALSJones is charged with conspiring to distribute cocaine. The judge throws out only the data from when the Jeep sat in the garage at his home; everything from public streets comes in. A first trial in October 2006 ends with a hung jury on the conspiracy count. At a second, the GPS data ties Jones to a stash house holding $850,000 in cash and 97 kilograms of cocaine. The jury convicts. The sentence: life in prison.
2010The federal appeals court in D.C. reverses the conviction, ruling that the warrantless GPS tracking violated the Fourth Amendment. The government goes to the Supreme Court. It admits it didn’t comply with the warrant — and argues it never needed one.
JAN 23, 2012All nine justices side with Jones: attaching the device and using it to monitor the Jeep was a search. But they split 5–4 over the reason, and that split is the part people still argue about.
The Question the Court Faced in United States v. Jones
The Jeep drove on public roads. Anyone on a sidewalk could have seen where it went. And an earlier case, United States v. Knotts (1983), had said a person traveling on public roads has no reasonable expectation of privacy in those movements. So the question: when the government secretly attaches a GPS device to someone’s vehicle and uses it to follow that vehicle for four weeks, has it done something the Fourth Amendment covers — or just watched what was already in plain view?
What the Court Decided in United States v. Jones
It was a search — and Justice Scalia’s majority got there without ever asking what Jones expected to keep private:“The Government physically occupied private property for the purpose of obtaining information.”— Justice Scalia, for the Court
That was enough. The Fourth Amendment protects people in their “persons, houses, papers, and effects,” and a vehicle is an “effect.” Until the second half of the 20th century, the Court’s cases tied the Amendment to property: physically intrude on a protected thing to gather information, and you’ve searched. Then Katz v. United States (1967) added a test built on privacy expectations. The government argued Katz had replaced the property rule. Scalia said no — the Katz test was “added to, not substituted for” it. Agents put a device on the Jeep to collect information. Search. Four justices agreed with the result but not the route. Justice Alito, joined by Justices Ginsburg, Breyer, and Kagan, called the trespass approach artificial — it offers nothing when police can track a car without touching it. He would have asked the Katz question instead. His answer: brief monitoring on public streets is fine, but society has never expected police to “secretly monitor and catalogue every single movement of an individual’s car for a very long period.” He named no exact cutoff, writing only that “the line was surely crossed before the 4-week mark.” Justice Sotomayor joined Scalia’s opinion — giving it the fifth vote — and wrote separately to say Alito had a point too:
“GPS monitoring generates a precise, comprehensive record of a person’s public movements that reflects a wealth of detail about her familial, political, professional, religious, and sexual associations.”— Justice Sotomayor, concurring
She also went further than anyone else, suggesting the Court may need to rethink the third-party doctrineThird-party doctrine: the rule that information you voluntarily hand to a company, like the phone numbers you dial, gets no Fourth Amendment protection., an approach she called “ill suited to the digital age.” No one dissented. And notice what the Court did not decide. The government had a backup argument: even if this was a search, it was a reasonable one, because agents had strong grounds to suspect Jones. The Court wouldn’t hear it, because the government hadn’t raised it in the lower court: “We consider the argument forfeited.” So Jones holds that attaching and using the tracker is a search. It does not hold that a warrant is always required.
What United States v. Jones Means for You
✓ BECAUSE OF JONES
- When police physically attach a tracker to a car to gather information, that is a Fourth Amendment search — not a free move
- “It only showed public roads” stopped being a complete answer once the government touches your property to do the tracking
- There are two ways to show a search: a physical intrusion on your property, or a violation of a reasonable expectation of privacy
- Five justices went on record that long-term location tracking raises privacy problems even without a trespass — the idea Carpenter later built on
✗ JONES DOESN’T MEAN
- Police can never use a GPS tracker — this case began with a warrant that allowed one, if agents had followed it
- A warrant is always required — the Court called it a search and stopped there
- Being followed the old-fashioned way is a search — the majority said watching with your eyes is not
- Phone tracking was settled — nothing gets attached when police ask a company for records; that fight came later
- Jones walked free — he won at the Supreme Court and still ended up with a 15-year sentence
Questions People Ask About United States v. Jones
Did the Court say police need a warrant to use a GPS tracker?
Not exactly — and this is the most common mistake people make about Jones. The Court held that attaching the device and using it to monitor the vehicle is a search. But the government also argued this search was reasonable without a valid warrant, and the Court refused to rule on that because the argument came too late. Jones answers “is this a search?” It leaves “when is this search legal?” open.
Why did all nine justices agree on the result but split on the reason?
Scalia’s five saw a property problem: agents put something on a man’s Jeep. Alito’s four saw a privacy problem: agents recorded a month of a man’s life. Here both roads led to the same place. In a case with no physical device, they don’t. Alito even teased the majority’s history lesson: the closest thing in 1791 would have been a constable hiding inside someone’s coach — which would have taken a very big coach or a very small constable.
What if police track me without touching anything — like through my phone?
Jones left that open on purpose. The majority said tracking done only through electronic signals, with no trespass, would be judged under the Katz privacy test. Then the question arrived. In Carpenter v. United States (2018), the Court held that getting a person’s historical cell-site location records is a search that generally requires a warrant — leaning on the Jones concurrences to get there. In June 2026, Chatrie v. United States held that police also conducted a search when they got a man’s location data from Google. For the practical version, see can police track your phone?
Why does Justice Sotomayor’s opinion get quoted so much?
Because she described the future. Writing only for herself, she explained how location data maps a person’s whole life, how cheap it is to collect, and how badly the old “you shared it, you lost it” rule fits a world where everyday tasks hand data to companies. Two years later, Riley v. California (2014) quoted her GPS sentence while explaining why police generally need a warrant to search a phone. A one-justice concurrence isn’t binding law. But it can show where the Court is headed.
Whatever happened to Antoine Jones?
He did not go home. The ruling wiped out his conviction and life sentence, but prosecutors could try him again without the GPS data — and they did. At his next trial, Jones represented himself with help from court-appointed lawyers, and in March 2013 the jury deadlocked and the judge declared a mistrial. On May 1, 2013, he pleaded guilty to a single drug conspiracy count and was sentenced to 15 years, with credit for the time he had been locked up since 2005.
Key Terms in United States v. Jones, Explained
Search — government action the Fourth Amendment covers. Step one is asking whether something is a search; step two is whether it was reasonable.
Effects — the Fourth Amendment’s word for personal property. A vehicle is one.
Trespass — a physical intrusion on someone’s property; the majority’s reason the tracker was a search.
Reasonable expectation of privacy — the test from Katz; the four concurring justices would have decided the case this way.
Third-party doctrine — the rule that information you share with a company loses protection; Justice Sotomayor questioned it here.
Concurring in the judgment — agreeing with who wins, but not with the majority’s reasoning.
Forfeited argument — a point a party failed to raise in the lower court. It’s why Jones never reached the warrant question.
Cases Connected to United States v. Jones
Katz v. United States (1967)The privacy test Jones refused to treat as the only one. Katz said the Fourth Amendment protects people, not places; Jones said the older property protection never went away.Read the full case → Carpenter v. United States (2018)The sequel. No device, no trespass — just a phone company’s records. The Court picked up the Jones concurrences and held that getting them is a search.Read the full case → Riley v. California (2014)Two years after Jones, the Court quoted Justice Sotomayor’s GPS warning while holding that police generally need a warrant to search a phone.Read the full case →United States v. Knotts (1983)The case the government relied on: police followed a beeper hidden in a container of chloroform. Jones set it apart — that beeper went in with the container owner’s consent, before Knotts ever had it.
Chatrie v. United States (2026)The newest link in the chain: police conducted a search when they obtained a man’s location data from Google through a geofence warrant.
What’s Still Undecided After United States v. Jones
Jones answered one question and handed the rest to the future. As of October 2026:
- When a tracker search is legal — Jones held that attaching and using a GPS device is a search and stopped there. It never said what makes that search reasonable.
- How long is too long — Justice Alito’s group said four weeks crossed the line but named no number. Carpenter later held that seven days of cell-site records was enough to count as a search, without saying whether a shorter stretch would be.
- Tracking with no trespass and no phone — license plate cameras, long-running video cameras, and whatever comes next. The Supreme Court has not ruled on these; lower courts are taking them one case at a time.
- Geofence warrants — Chatrie held in June 2026 that getting a person’s location data from Google is a search, but sent the case back to decide whether the warrant was specific enough and backed by probable cause.
Why this page exists: Jones usually gets squeezed into one line — “GPS tracking needs a warrant” — and that isn’t quite what the Court said. The real story is more useful: nine justices, one result, two reasons. Every fact about the ruling comes from the Court’s own opinion — linked below so you can check us.
The Bottom Line on United States v. Jones
A warrant followed one day late, a small device under a Jeep, and 28 days of data gave the Court its GPS case. The holding is narrow and solid: when the government puts a tracker on your property and uses it to follow you, that’s a search. The bigger idea came from the justices who wrote separately — that a long enough record of where you go is a record of who you are. Jones didn’t finish that thought. Carpenter picked it up, and courts are still working on it. Now you know.Your practical guideCan police track your phone? → The sequelCarpenter v. United States → More casesBrowse all court case files →
Sources
Primary sources:- United States v. Jones, 565 U.S. 400 (2012) — full opinion — supreme.justia.com
- United States v. Jones — argument audio and case summary — oyez.org
- Carpenter v. United States, 585 U.S. 296 (2018) — supreme.justia.com
- Chatrie v. United States, No. 25-112 (2026) — supreme.justia.com
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