A case before the Supreme Court could determine whether law enforcement can use your phone's location data to find you first and suspect you later—effectively inverting the constitutional standard of probable cause.
At the center of the case are geofence warrants—digital dragnets that identify everyone near a crime scene, then treat them as potential suspects. It's the "collect first, justify later" approach to surveillance, and it could fundamentally change how the Fourth Amendment applies to digital evidence.
How Geofence Warrants Work
When police investigate a crime, they can request that Google (or Apple, or any location service provider) hand over data on every device that was within a specific geographic area during a specific time window. Not suspects. Not witnesses. Everyone.
If your phone was near a robbery at 2 PM on Tuesday—maybe you were buying coffee next door, or stuck in traffic, or walking past—you're now in law enforcement's database. Police then sift through this haystack of location data looking for patterns, alibis, or people they want to investigate further.
The constitutional problem: traditional warrants require probable cause that a specific person committed a crime. Geofence warrants flip this—they demand data on everyone in an area, then look for suspects.
The Scale of the Issue
This isn't theoretical. Law enforcement agencies issued over 11,000 geofence warrants in 2021 alone, according to data from Google's transparency reports. That number has grown every year.
A single warrant can sweep up hundreds or thousands of people. In one case, a geofence warrant for a Phoenix homicide identified over 1,500 devices. The vast majority of those people had nothing to do with the crime, but their location data is now in a criminal investigation database.
The Legal Arguments
Civil liberties groups argue this violates the Fourth Amendment's prohibition on unreasonable searches. You can't get a warrant to search every house in a neighborhood hoping to find evidence—that's the definition of a "general warrant," the exact thing the Fourth Amendment was written to prevent.
Law enforcement counters that location data is voluntarily provided to third parties (Google, Apple) and therefore not protected by the same privacy standards. They argue geofence warrants are essential investigative tools for crimes with no identified suspects.
The Supreme Court has been grappling with how Fourth Amendment protections apply to digital data. In the 2018 Carpenter v. United States decision, the Court ruled that accessing historical cell phone location data requires a warrant. But geofence warrants are a different animal—prospective, broad, and designed to identify suspects rather than track known ones.
What's at Stake
If the Court upholds geofence warrants, we're entering an era where your phone's location history can make you a suspect in crimes you didn't commit, simply because you were in the wrong place at the wrong time. Attend a protest? You're in the database. Walk past a crime scene? You're a potential suspect.
If the Court strikes them down, law enforcement loses what they consider a critical tool for solving crimes in the digital age—a way to generate leads when traditional investigative methods hit dead ends.
Either way, the decision will define whether the Fourth Amendment's protections extend to the location data your phone generates constantly, or whether that data exists in a legal gray zone where privacy protections don't fully apply.
The Court hasn't announced when it will hear arguments, but this case will shape surveillance law for the next decade.
