The Supreme Court ruled Monday that police cannot use mass location data sweeps to identify criminal suspects without violating the Fourth Amendment, handing down a 6-3 decision that curbs a growing law enforcement tool known as a geofence warrant.
The ruling, written by Justice Elena Kagan, says that a person who carries a cellphone has a reasonable expectation of privacy over their location data, even when that data is stored by a third-party company such as Google.
“A cell-phone user is not to be viewed as sharing private information with third parties which then can be freely passed on to the government, just by doing the ordinary things cell-phone users do,” Kagan wrote.
The case centered on Okello Chatrie, who was convicted of robbing a credit union in the Richmond, Virginia, suburbs in May 2019. He is currently serving nearly 12 years in federal prison after pleading guilty.
Investigators had identified Chatrie using a geofence warrant, a type of reverse warrant that compels technology companies to hand over data from every device within a defined geographic area at a specific time. In Chatrie’s case, law enforcement demanded anonymized data from all phones within a 17.5-acre radius around the bank, then narrowed the list to identify the robbery suspect.
The Supreme Court sent the case back to the Fourth Circuit Court of Appeals to determine whether the specific warrant used to identify Chatrie met the Fourth Amendment’s requirements for particularity and probable cause. Monday’s ruling does not automatically overturn Chatrie’s conviction.
“Because this is a ‘court of review, not a first view,’ the Court leaves it up to the Court of Appeals to decide whether, at each step of the search process, the warrant satisfied the Fourth Amendment’s requirements of particularity and probable cause,” Kagan wrote.
Justices Samuel Alito, Clarence Thomas and Amy Coney Barrett dissented. The remaining six justices, including Chief Justice John Roberts and Justices Brett Kavanaugh and Neil Gorsuch from the conservative wing, joined the majority.
The decision narrows the circumstances under which federal law enforcement can obtain cloud-stored location data without an individualized warrant tied to a specific suspect.
Geofence warrants have become increasingly common among law enforcement agencies over the past decade. Prosecutors argued that Chatrie had no reasonable privacy expectation because he voluntarily shared his location data with Google when he used his phone.
The high court rejected that argument. Chatrie’s district court had initially agreed his rights were violated but allowed the evidence anyway under the good-faith exception. The Fourth Circuit upheld that ruling before the Supreme Court took the case.
Law enforcement agencies that have relied on geofence warrants, including local police departments investigating everything from violent crime to Capitol riot participants, will now face stricter legal scrutiny when seeking that class of data.
