Google Geofence Warrants Are Dead—Supreme Court Heard Last One Monday

InnovationScienceGoogle Geofence Warrants Are Dead—Supreme Court Heard Last One MondayByLars Daniel,Contributor.Forbes contributors publish independent expert analyses and insights. Lars Daniel covers digital evidence and forensics in life and law.Follow AuthorApr 28, 2026, 09:18pm EDT--:-- / --:--This voice experience is generated by AI. Learn more.This voice experience is generated by AI. Learn more.Google Maps SOPA Images/LightRocket via Getty ImagesThe Supreme Court heard oral arguments Monday in Chatrie v. United States, the first time the justices have taken a geofence warrant case directly. A decision is expected before the term ends.The case is a strange one to land at the Supreme Court in 2026, because the technique it asks about no longer functions the way it did when the warrant in question was issued. Google ended its ability to respond to geofence warrants more than a year ago. The pipeline that produced more than 20,000 of these warrants between 2018 and 2020 is closed. The Court is ruling on a tool that, as a practical matter, is already gone.Here is what the tool was, how it worked, and why it stopped working.What A Geofence Warrant IsA traditional search warrant names a suspect or a place. The government has probable cause that a person committed a crime, and the warrant authorizes a search of that person's home, car or accounts.A geofence warrant works the other direction. The government has no suspect. It has a location and a time window. It asks Google to identify every device whose Location History placed it inside that area during that window. Google runs the query and returns anonymized device IDs. The government narrows the list and asks Google to de-anonymize a handful.MORE FOR YOUThe data is generated by Google Location History, the opt-in feature most people associate with Google Maps. Pre-cutover, that data could place a device within meters of its actual location at frequent intervals. That is closer to a GPS tracker than the cell t...