The U.S. Supreme Court ruled on Monday that law enforcement's use of sprawling warrants to collect large amounts of cellphone location data, known as geofence warrants, requires privacy protections under the Fourth Amendment. In a 6-3 decision, the court determined that police cannot simply demand the minute-by-minute location diaries kept by smartphones.
The ruling, with the majority opinion written by Justice Elena Kagan, applies individual constitutional protections to new technology. The case centered on a challenge by a Virginia man who was convicted of armed robbery after police used a geofence warrant to access location data near the crime scene. The court threw out the judicial decision involving the man's conviction.
The decision is a major win for digital privacy and privacy advocates, who had previously called the use of such warrants unconstitutional and sought an outright ban. The ruling limits a practice that has quietly spread through U.S. policing, which critics viewed as an unconstitutional dragnet.