Washington, D.C., March 02, 2026 (GLOBE NEWSWIRE) -- The New Civil Liberties Alliance filed an amicus curiae brief today in Chatrie v. United States urging the Supreme Court to rule that the government’s sweeping collection of location data via geofences offends the Fourth Amendment. Geofencing uses the location history of your cell phone or other digital devices to determine when you entered or left a specific area surrounded by virtual “fences.” Geofence warrants allow the government to gather the location histories of everyone who happened to be near the scene of a suspected crime at a particular time, no matter the reason they were in the vicinity. NCLA asks the Justices to overturn the ruling by the U.S. Court of Appeals for the Fourth Circuit, which rejected Okello Chatrie’s motion to suppress evidence based on a police geofence warrant that happened to capture his location.
The Supreme Court’s 2018 Carpenter v. United States ruling declared that people have a legitimate expectation of privacy in the whole of their movements over time, noting that an individual “does not surrender all Fourth Amendment protection” by going out in public. A person’s geofenced location history is precise and detailed, a window into his or her private life. When the government seizes that data, it is conducting a “search” that violates the Fourth Amendment right to keep one’s movements private.
Geofence warrants resemble the reviled “general warrants” of the colonial era, which motivated the Founders to pass the Fourth Amendment in the first place. They defy the Fourth Amendment’s requirement that warrants only be issued when there is probable cause and a description of “the place to be searched, and the persons or things to be seized.”
The Fourth Circuit held in this case that the police warrant’s taking two hours of Chatrie’s location history only showed a “single trip in isolation” and could not reveal “his habits routines and associations,” thus deciding it did not violate the Carpenter decision. But that reasoning mischaracterizes the logic of Carpenter and disregards how powerful geofence data is, dramatically understating how much it can reveal about a person’s life. Whether the data collected revealed something private is beside the point. It definitely had the potential to do so. The government has invaded Chatrie’s privacy either way. If nothing private was revealed, that’s just happenstance.
NCLA released the following statements:
“Geofence warrants are another example of the government’s attempt to exploit technological innovation to invade Americans’ privacy. They allow the government to search first and justify later. The Fourth Amendment forbids both this kind of ‘too permeating police surveillance’ and this clear inversion of the warrant requirement.”
— Andreia Trifoi, Staff Attorney, NCLA
“‘Round up the usual suspects!’ is a trope in the movies, signifying bad police work. Geofence warrants are the modern version of lazily pointing the finger at a group of possible perpetrators without a shred of other evidence.”
— Mark Chenoweth, President and Chief Legal Officer, NCLA
For more information visit the amicus page here.
ABOUT NCLA
NCLA is a nonpartisan, nonprofit civil rights group founded by prominent legal scholar Philip Hamburger to protect constitutional freedoms from violations by the Administrative State. NCLA’s public-interest litigation and other pro bono advocacy strive to tame the unlawful power of state and federal agencies and to foster a new civil liberties movement that will help restore Americans’ fundamental rights.
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Joe Martyak New Civil Liberties Alliance 703-403-1111 joe.martyak@ncla.legal
