A 6 3 ruling signaled serious constitutional doubt about 'geofence' warrants, which let police identify suspects by sweeping up location data on every phone in a crime scene area.
The US Supreme Court ruled 6-3 that individuals have a reasonable expectation of privacy in cellphone location data, making it generally subject to Fourth Amendment protection, a decision that casts doubt on the future use of broad "geofence warrants" that identify suspects by locating phones near a crime scene.
Writing for the majority, Justice Elena Kagan described the records as a "personal journal of a user's movements," analogizing the data to "emails, documents, photographs." That framing captures the constitutional concern: not just whether police may access a single data point, but whether they may reconstruct the chronicle of where a person has been over time.
The case arose from a Virginia credit union robbery investigation. Police used Google location data to identify Okello Chatrie as a suspect and secured his conviction. Under the ruling, that conviction will be reconsidered by lower courts.
What makes the decision structurally significant is the type of warrant at issue. Traditional search warrants run suspect-to-data: an investigator names a person, then seeks records tied to that person. Geofence warrants invert that sequence. Police define a geographic area around a crime scene, ask a provider such as Google for location data on every device that passed through it during a window, and use the resulting pool to identify potential suspects.
That reversal matters because it changes who is the subject of the search before anyone is named. When investigators sweep up the chronicles of every phone in an area, including bystanders who passed through, the Fourth Amendment question becomes whether the government may treat an entire neighborhood's movements as investigable by default.
The Court stopped short of striking down geofence warrants outright, instead signaling serious constitutional doubt and sending the Chatrie case back to Virginia courts for reconsideration under the new framework. The opinion did not draw a final warrant-probability-cause line, leaving lower courts to work out what probable cause looks like for location-history requests and when, if ever, exigent circumstances justify access without a warrant.
The ruling continues a doctrinal shift the Court began in Carpenter v. United States (2018), which first held that cell-site location information is protected by the Fourth Amendment. Where Carpenter addressed targeted requests for one suspect's records, the new decision applies the same privacy logic to a much broader investigative tool that has become common since Carpenter did not address it directly.
For ordinary readers, the practical takeaway is straightforward: the places your phone has been are not, by default, a public record. They are constitutionally protected information, and police generally need a warrant to obtain them. What remains unsettled is how often warrants will issue, what showing of probable cause will suffice, and how lower courts will treat the geofence-warrant cases already working through the system.