The Supreme Court ruled Monday in Chatrie v. United States that, when law enforcement used a geofence warrant directing Google to produce location data for every cellphone near a Virginia bank during a 2019 robbery, they conducted a “search” under the Fourth Amendment. By a 6-3 vote, the Court sent the case back to the lower court to determine whether the search was “reasonable.” Justice Elena Kagan, writing for the majority, held that an individual retains a reasonable expectation of privacy in cell phone location records even when a third-party tech company holds them.

The holding matters. What matters more is what the Court left unanswered.