The US Supreme Court ruled 6-3 that geofence warrants triggering police access to smartphone location data require Fourth Amendment protections, rejecting the government's argument that users waive privacy rights when carrying phones in public spaces. Justice Elena Kagan authored the majority opinion, establishing that individuals maintain a reasonable expectation of privacy in their location records regardless of third-party storage.

The case arose from Chatrie's armed bank robbery in Richmond, Virginia, where he stole $195,000 before law enforcement tracked him through Google's location history feature. Chatrie's attorneys successfully argued that the warrant was overly broad, sweeping in data from countless innocent users rather than targeting specific suspects. The majority noted that geofence warrants frequently capture thousands of users across private homes, churches, and medical facilities without individualized suspicion.

Google acknowledged in legal filings that these searches often ensnare innocent parties, with warrants covering busy roads and apartment buildings where law enforcement lacks probable cause. Justice Sonia Sotomayor warned that even brief location monitoring reveals intimate details about personal associations, including visits to therapists, abortion clinics, and religious services.

Law enforcement agencies rely on geofence warrants to identify suspects and witnesses when traditional investigative methods fail, but must now meet constitutional standards for probable cause and particularity. The ruling clarifies that converting consumer services into surveillance tools requires judicial oversight, marking the Court's first major digital privacy decision since 2018.