The Supreme Court Just Ruled Your Phone Can't Be an Open Search Target
The justices held that police conduct a Fourth Amendment search when they obtain Google Location History—even from a third party, even for just two hours
In May 20, 2019, an armed man walked into Call Federal Credit Union in Midlothian, Virginia, threatened employees with a firearm, and stole $195,000 from the vault. Police had surveillance footage and witness accounts but no suspect. So they did something that would have been unimaginable a generation ago: they drew a digital circle around the crime scene and asked Google to identify every person whose phone placed them inside it.
The Supreme Court ruled Monday that this technique — known as a geofence warrant— constitutes a Fourth Amendment search. Writing for a 6-3 majority in Chatrie v. United States, Justice Elena Kagan held that individuals have a reasonable expectation of privacy in their cell phone location records, and that police intrude on that constitutionally protected interest when they demand the information from a tech company, even if the data covers only a short period.
The decision sends the case back to lower courts to determine whether the specific warrant used was constitutionally valid, but it rejects the government’s core argument: that two hours of precise location history stored with Google falls outside Fourth Amendment protection entirely.
The Ruling and What It Changes
The Court’s answer rests on its 2018 decision in Carpenter v. United States, which held that accessing cell-site location information (CSLI) constitutes a search because individuals have a reasonable expectation of privacy in the whole of their physical movements. Kagan wrote that Google Location History implicates privacy interests even more than CSLI: it pinpoints location within roughly 20 meters rather than within sectors of one-eighth to four square miles, records location every two minutes rather than sporadically, and can estimate elevation to reveal which floor of a building a phone is on. It also functions, in Google’s own description, like a personal journal—users consult it to remember a restaurant, a friend’s home, or a vacation route.
The government argued that because users can choose not to give companies like Google their location data, that data is not constitutionally protected. Kagan rejected that logic. Google repeatedly prompts users to enable Location History, often warning that devices will not “work correctly” otherwise, without disclosing in that prompt how frequently location would be recorded, how precise it would be, or how it might be given to the government.
“A cell-phone user is not to be viewed as sharing private information with third parties just by doing the ordinary things cell-phone users do,” the majority wrote.
The Requirements Were Not Met
The ruling forces police and prosecutors to meet familiar Fourth Amendment requirements when they seek geofence data: probable cause, particularity, and a scope tailored to the justification for the search. The Court specifically flagged weaknesses in the Virginia warrant’s later steps, where officers could choose which anonymized users deserved more scrutiny with very little guidance from the magistrate.
Future warrants will need to answer questions that are no longer optional: Why this radius? Why this timeframe? Why is there probable cause to believe the database contains evidence? Who decides which users move to the next stage? What happens to everyone else’s data?
The Loophole the Court Didn’t Close
The decision carries particular weight because Google has already changed the playing field. In December 2023, the company announced that Maps Timeline data would move to on-device storage, with cloud backups encrypted so that even Google could not read them. As of July 2025, Google told the Supreme Court, Location History data previously stored on its servers had been deleted or migrated to on-device storage, and Google could no longer respond to geofence warrants based on Location History.
That does not make the ruling obsolete. It sets the legal framework for the next surveillance fight. Police may turn to telecom companies, app developers, vehicle telematics, license plate readers, payment apps, or — most troubling — commercial data brokers. The data broker problem is especially acute because it lets agencies buy what they might otherwise need legal process to obtain.
What It Means for Americans
The ruling matters for Americans who will never rob a bank, attend a protest, or visit a politically sensitive location. Geofence warrants commonly cover private homes, apartments, hotels, and places of worship, according to information Google provided to the Court. A geofence around a bank can sweep in a church next door. A geofence around a riot can sweep in journalists, legal observers, and peaceful protesters. A geofence around an abortion clinic, synagogue, mosque, gun show, union hall, political meeting, or hospital can reveal facts the government has no business collecting without specific constitutional justification.
The point of the Fourth Amendment is not to protect only the innocent or only the guilty. It is to preserve a civic order in which the government must justify intrusion before it rummages through the private patterns of ordinary life. In a democracy, that principle matters whether you live in Virginia or Vermont, whether you use Google Maps daily or never open the app. The Constitution requires that police suspect you before they search you — not search first and decide whom to suspect later.
Today's technology would have been the stuff of dreams for tyrants like Lenin, Stalin, Hitler, Mao, and all the others.