The Supreme Court ruled Monday in Chatrie v. United States that a “geofence warrant” counts as a “search” under the Fourth Amendment.

In a 6-3 decision, the majority opinion, authored by Justice Elena Kagan, said that police accessing someone’s Location History through Google is a Fourth Amendement search since “an individual has a reasonable expectation of privacy in his cell-phone location information.” Chief Justice John Roberts as well as Justices Sonia Sotomayor, Brett Kavanaugh and Ketanji Brown Jackson joined the majority opinion, with Justice Neil Gorsuch filing a separate opinion but concurring in judgment. Justices Samuel Alito, Clarence Thomas and Amy Coney Barrett dissented. (RELATED: Supreme Court Rules Illegals Outside The US Have Not Arrived In The US)

“[T]he [Fourth] Amendment was designed ‘to place obstacles in the way of a too permeating police surveillance,'” Kagan said in her opinion. “Whatever the form of an attempted incursion, the Fourth Amendment protects Americans’ long-held conviction that no government official should have free access to the most closely kept aspects of their lives.”

Petitioner Okello Chatrie was arrested for robbing a credit union in Midlothian, Virginia, in. 2019 case. He later pleaded guilty and was sentenced in 2022, a Justice Department statement said Police only knew that the suspect was talking on a cellphone, so they tracked him down using Location History information they obtained from Google after applying to a Virginia magistrate for a geofence warrant, according to the opinion.

The warrant included a three-step process to narrow down the suspect, Kagan wrote. In the first step, Google would only provide the anonymized location data for all the cellphones within 150 meters of the crime from 30 minutes before it occurred to 30 minutes after. In the second step, police would narrow down the likely suspects from the information they had and Google would provide more anonymized information on the cellphones’ locations for two hours around the time of the crime. Finally, the police narrowed the list down to three cellphones and Google provided identifying information on all three users.

Police identified Chatrie as the suspect and a federal grand jury later indicted him on robbery and firearms offenses in connection with the incident, according to the opinion. Chatrie petitioned, alleging that the information they obtained from Google fell under the Fourth Amendment and the warrant was invalid.

While the court granted the first part of the petition, it sent the decision back to the lower courts to decide whether the warrant was valid and could justify each step of the process law enforcement used, according to Kagan’s opinion.