Supreme Court Says Police Need a Warrant for Geofence Location Sweeps, 6-3.

The Supreme Court ruled 6-3 on June 29, 2026, that police need a warrant before they can sweep up cellphone location data to find everyone who was near a crime scene. The court held that these “geofence” searches are a search under the Fourth Amendment, and it rejected the Trump administration’s argument that no warrant is required, NPR reported. Justice Elena Kagan wrote the majority opinion.

What a Geofence Warrant Is

A geofence warrant works backward from a normal one. Instead of naming a suspect, police draw a box around a place and a window of time and ask a company like Google for every device that was inside it.

The result is a list of everyone in the area, not just the person police are after. A bank robbery on a busy street can sweep in commuters, delivery drivers, and people asleep in nearby apartments. The case the court decided, Chatrie v. United States, grew out of exactly that, a Virginia bank robbery where the conviction relied on Google geofence data.

What the Court Held

The majority held that people have a reasonable expectation of privacy in their phone’s location history, even when a third-party company holds it.

“An individual has a reasonable expectation of privacy in records about his cell phone’s location, and police intrude on that constitutionally protected interest when they demand the information.”

Justice Elena Kagan, majority opinion

The ruling builds on Carpenter v. United States, the 2018 case that required a warrant for historical cell-site location records.

The court did not decide whether the specific warrant in Chatrie’s case was valid, and sent that question back to the lower court. The headline is the rule it set, that a geofence sweep requires a warrant at all.

The Loophole the Ruling Leaves Open

The decision covers what the government demands from a company. It says nothing about what the government buys.

Federal agencies, including immigration enforcement and the FBI, purchase detailed location data on millions of Americans from commercial data brokers. No warrant, no court, just a contract. They can buy the same information the court just said requires a warrant to seize. The Fourth Amendment Is Not For Sale Act would close that gap by requiring a warrant before the government buys it.

Why It Matters

A geofence sweep treats everyone near a place as a possible suspect. Requiring a warrant puts a judge between the police and a list of innocent people’s movements, which is the point of the Fourth Amendment.

The win is real, but it is partial. The same government that now needs a warrant to demand your location can still buy it on the open market, and the larger fight over warrantless surveillance of Americans is still unresolved in Congress. A right the government can purchase its way around is only half a right.

What You Can Do Now

Use the letter below to ask your members of Congress to pass the Fourth Amendment Is Not For Sale Act, so the government cannot buy the location data it now needs a warrant to seize.
Call your senators and representative at (202) 224-3121. Tell them the geofence ruling is a good start, and you want the data-broker loophole closed so it cannot be sidestepped.
Lock down your own location data. Turn off location history in your phone and app settings, and review which apps can see your location. The less data the brokers hold, the less there is to buy or seize.