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You can get dragged into a police investigation by proximity alone — for now

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Why This Matters

The Supreme Court's consideration of geofence warrants highlights the growing privacy concerns surrounding location data and law enforcement's ability to access it. The case could set a precedent for how digital privacy rights are protected in the age of pervasive technology, impacting both consumers and the tech industry. As companies and courts grapple with these issues, the outcome will influence future privacy policies and surveillance practices.

Key Takeaways

A years-old bank heist may soon have major privacy implications for every American who owns a cellphone. On Monday, the Supreme Court heard arguments in Chatrie v. United States, a case involving police’s use of controversial “geofence warrants” to find and arrest Okello Chatrie, the suspect of a 2019 bank robbery outside Richmond, Virginia. At stake is how private your location data — and any other information you store with a large tech company — actually is.

Chatrie was tracked down via the Location History feature on Google Maps, which can identify a person’s location within three meters and refreshes every two minutes. Police served Google with a warrant asking for data on anyone who had been within 300 meters of the Call Federal Credit Union at the time of the robbery, and made subsequent requests for users’ information until they identified Chatrie as the prime suspect.

Chatrie’s attorney argues that the geofence inquiry constituted an unreasonable search and seizure and therefore violated the Fourth Amendment. A federal district court agreed, determining that police didn’t have probable cause for a geofence warrant — but the court ultimately sided with the government, using the “good faith exception” to justify the legality of the otherwise unconstitutional search. A federal appeals court not only upheld the government’s position but also ruled that the Fourth Amendment hadn’t been violated at all, since Chatrie had voluntarily shared his location information with Google. Following today’s arguments, the Supreme Court will issue a ruling in the coming months.

Google stopped storing Maps users’ location history in the cloud in 2024, citing privacy concerns — a change that led some justices to question why the court was taking up this issue in the first place. “This involves a Google feature that doesn’t exist any longer,” Justice Samuel Alito said during Monday’s oral arguments. “You’re asking for a law review article on a subject that is largely unexplored by our precedents.”

But plenty of other companies track users’ location data: Uber, Lyft, and Snap, to name a few, not to mention the scores of other apps that monitor and store information on users’ whereabouts. “Chatrie could have fairly major implications in other digital search cases, especially ‘reverse searches’ like this case where police do not have an identified suspect, account, or device,” Andrew Crocker, the surveillance litigation director at the Electronic Frontier Foundation, told The Verge. (The EFF filed an amicus brief in the case.)

Detectives sent Google a geofence warrant after hitting a dead end in their 2019 investigation of the robbery. Google first provided semi-anonymized information on 19 users, according to The New Republic. The detective investigating the case then sent a follow-up request for nine users’ data, providing no explanation on “why he chose the nine accounts,” and then asked Google to de-anonymize three of those accounts. This information led police to Chatrie.

Adam Unikowsky, Chatrie’s attorney, described these actions as “bad police work.” Some justices seemed skeptical. Justice Brett Kavanaugh, for example, said the police work in the Chatrie investigation “should be applauded.”

One of the questions at the heart of the case is whether accessing geofence information counts as a “search” at all. The court uses two methods to assess this, said Brent Skorup, a legal fellow at the libertarian Cato Institute, which submitted an amicus brief in the case. The first involves property interests — whether a trespass was committed during a search of a house, for instance, or someone’s diary. The second involves whether basic privacy rights were violated, even in cases where no property is at stake.

The core argument in Chatrie, Skorup explained, was that Chatrie owned his location history records and Google was holding them on his behalf in something akin to a virtual locker, just like a bank holds someone’s money. “We give our property to third parties all the time,” Skorup said. “If you mail a letter or put something in a safe deposit box, you still own the property even if you’re entrusting it to others.”

On Monday, most justices seemed skeptical of the property argument. But Chatrie’s attorneys made another argument using what’s known as the Katz test. Under the precedent set by Katz v. United States, even if no property is involved, a search can occur if it violates a person’s expectation of privacy — including instances where police bugged a telephone booth, or obtained cellphone tower records, both without a warrant. The latter was the subject of Carpenter v. United States, a 2018 case in which the court ruled that police must generally get a warrant to seize cellphone tower location records.

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