Supreme Court Says App-Generated Location History Can Be a Fourth Amendment Search; Geofence Warrant Sent Back to Lower Court

The Supreme Court ruled Monday that obtaining a person’s phone location history can amount to a search under the Fourth Amendment, extending constitutional privacy protection beyond cellphone tower records to app-generated location data stored by a technology company.

But the justices did not decide whether the specific geofence warrant used in the case was lawful. Instead, the court vacated the 4th U.S. Circuit Court of Appeals’ judgment and sent the case back, leaving lower courts to decide whether the warrant satisfied the Constitution’s probable-cause and particularity requirements and whether the evidence should be kept under the good-faith exception.

The case, Chatrie v. United States, grew out of a May 20, 2019, credit-union robbery in Midlothian, Virginia, near Richmond. On June 14, 2019, police sought a geofence warrant ordering Google to identify devices that had been within a 150-meter radius of the crime scene around the time of the robbery, using the company’s multistep process tied to users’ Location History data.

A geofence warrant does not begin with a known suspect. Instead, investigators ask a company to identify devices that were inside a defined area during a set period of time, then narrow the list from there.

Justice Elena Kagan wrote the majority opinion, joined by Chief Justice John Roberts and Justices Sonia Sotomayor, Brett Kavanaugh and Ketanji Brown Jackson. Jackson filed a concurrence joined by Sotomayor. Justice Neil Gorsuch concurred in the judgment. Justices Samuel Alito and Amy Coney Barrett dissented.

The ruling is the court’s first major digital-surveillance decision since Carpenter v. United States in 2018, which held that police generally need a warrant to obtain historical cell-site location information from a phone company. In Monday’s decision, the court said the same privacy logic can apply to location records generated by smartphone apps and stored by a third-party company, even when the tracking is shorter-term.

“We hold that they did because an individual has a legitimate expectation of privacy in his cell-phone location data,” the majority said.

The court also rejected the idea that data loses constitutional protection simply because it sits on a company’s servers rather than on a phone in a person’s pocket. “Location History resembles other private materials — e.g., emails, documents, photographs, or calendars — that even if stored on Google’s servers, a user reasonably views as his own and expects to be shielded from the ‘inquisitive eyes’ of the government,” the majority said.

Kagan’s opinion also pointed to the role apps play in everyday life, saying “the point of carrying smartphones is to use what is on them.”

The decision may have a narrower immediate effect on new Google geofence demands than its constitutional language suggests. Google announced in December 2023 that Maps Timeline, formerly called Location History, would move to on-device storage by default, writing that “Timeline will soon be saved on your device … when you first turn on Location History, the auto-delete control will be set to three months by default.” Google and later government summaries said that by July 2025, the company no longer had the centrally stored Location History database needed for the older style of mass geofence requests.

That means the case’s broader importance may lie less in old-style Google requests than in the court’s treatment of app- and cloud-based records more generally.

Before the Supreme Court took the case, a federal district court in Virginia ruled in 2022 that the warrant violated the Fourth Amendment but allowed the evidence under the good-faith exception, which can let prosecutors use evidence when officers reasonably relied on existing law. The 4th Circuit, sitting en banc in 2025, affirmed on good-faith grounds.

Monday’s ruling does not bar geofence warrants across the board, and it does not overturn Chatrie’s conviction. Instead, the case now returns to the 4th Circuit, which must decide the unresolved questions the justices left open: whether this warrant was sufficiently particular, whether it was supported by probable cause and whether suppression is warranted despite the government’s good-faith argument.