Okello Chatrie v. United States of America

Okello Chatrie is challenging the use of a geofence warrant to obtain his device location information, which was subsequently used to arrest and charge him with robbing a bank. On February 27, the Brennan Center joined the Center for Democracy and Technology, Surveillance Technology Oversight Project, and Defending Rights & Dissent to file a friend-of-the-court brief in the Supreme Court in support of Chatrie’s challenge. The brief argues that electronic location data is protected by the Fourth Amendment’s warrant requirement, that the overbroad geofence warrant fails to satisfy the Fourth Amendment’s particularity requirement, and that approving this warrant would open the door to a variety of “reverse search” warrants that would chill speech and association.

On May 20, 2019, a bank in Virginia was robbed. As part of the investigation into the incident, local police obtained a “geofence” warrant, which led them to allege that Chatrie committed the robbery.  

A geofence warrant requires a company that collects users’ location data and stores it in the cloud to turn over information about all the devices that were in a specified geographic area during a particular time. It typically follows a three-step process: First, the company provides anonymized data on all phones in a specified area; second, it provides location data outside the geofence area for a subset of requested phones; and third, the company provides account information for a narrowed number of devices.  

In this case, local police sought location data from Google for devices in the area around the robbed bank. They first obtained an anonymized list of all the devices present over the course of an hour in a 17.5-acre area — a broad area encompassing large public spaces, including a church. Without returning to seek judicial approval, the police then requested the location data for a subset of phones, seeking their movements outside the 17.5-acre area over the course of an additional hour. Police then received deanonymizing account information about three of those devices, one of which belonged to Chatrie.  

While the district court ruled that this geofence warrant violated the Fourth Amendment, the Fourth Circuit found that Chatrie had no reasonable expectation of privacy in his location information because he had voluntarily given it to Google. In an en banc review, the full Fourth Circuit split 7–7 on whether a search had occurred. Meanwhile, the Fifth Circuit ruled in another case that geofence warrants are inherently overbroad and violate the Fourth Amendment. The Supreme Court will now decide whether the geofence warrant utilized in this case violated the Fourth Amendment. Oral argument is set for April 27, 2026.

First, the brief argues that the Fourth Amendment protects individuals from warrantless surveillance of their movements. Tracking cell phone location data through geofence warrants allows police to travel back in time to reveal an individual’s precise whereabouts — including sensitive locations like their home, work, doctor’s office, and place of worship — in ways that are impossible with traditional investigative techniques. To secure the “privacies of life” against “arbitrary power,” the government must obtain a warrant to collect this electronic location data.

Second, the brief argues that the geofence warrant in this case fails to meet the Fourth Amendment’s probable cause and particularity requirements. Rather than targeting an individual based on particularized suspicion, the geofence warrant gathered location information on a broad swath of people in order to develop that suspicion.

Finally, the brief warns that authorizing this type of geofence warrant would enable a new class of “reverse search” warrants that would chill First Amendment rights to speech and association. We explain how these warrants, for example, may enable dragnet searches for everyone who ran a web search using certain terms, watched a specific video, or issued a prompt to an AI chatbot. Upholding the overbroad geofence warrant risks facilitating those “reverse search” warrants that create immense risks to privacy and First Amendment-protected activities.  

For all these reasons, the brief urges the Court to reverse the judgment of the Fourth Circuit and find the geofence warrant unconstitutional.