The Supreme Court on Monday hears a landmark case testing whether police can use geofence warrants to sweep up location data from every cellphone near a crime scene. The case stems from a 2019 robbery at Call Federal Credit Union in Midlothian, Virginia, where an armed suspect stole $195,000 and fled before officers arrived. Detectives used the controversial technique to identify Okello T. Chatrie, now 31, who was convicted and is serving a nearly 12-year sentence.

Geofence warrants work by drawing a virtual boundary around a crime scene and compelling tech companies like Google to provide data on every device in that area during a specific time. Critics argue this amounts to a fishing expedition that violates the Fourth Amendment's protection against unreasonable searches. Chatrie's lawyer argues the warrant was overly broad, allowing the government to "search first and develop suspicions later" in violation of constitutional protections.

Google stopped responding to geofence warrants last year because it no longer stores such data centrally, but law enforcement has made similar requests to Apple, Lyft, Snapchat, Uber, Microsoft and Yahoo. The case follows the court's 2018 Carpenter ruling, which required warrants for cell tower location data. A federal judge originally found the warrant violated the Fourth Amendment but allowed the evidence because the officer acted in good faith.

The Supreme Court agreed to hear the case after a full Fourth Circuit court split 7-7, leaving Chatrie's conviction in place. The justices must now determine whether traditional privacy protections apply to the vast amounts of location information collected by technology companies.