Written by: Paige Henze 

Megan Graham, clinical professor, managing attorney for the Legal Clinic, and director of the Technology Law Clinic at the University of Iowa College of Law, filed an amicus brief in the U.S. Court of Appeals for the Fourth Circuit on behalf of herself and five other law professors in United States v. Chatrie. The case concerns geofence warrants and was remanded to the Fourth Circuit after the U.S. Supreme Court ruled that geofence queries are searches under the Fourth Amendment in June.  in June. 

Geofence searches involve law enforcement seeking information about devices located within a certain geographic area during a specific period of time. Unlike traditional searches that begin with a particular suspect, reverse searches (like geofence queries) can involve searching large amounts of data to identify potential suspects.

Graham and the other professors argue that the Fourth Circuit’s treatment of geofence warrants could have implications far beyond location data, raising Fourth Amendment concerns by exposing the sensitive information of many people without individualized suspicion. If the case’s geofence warrant is found constitutional, they warn that a door is opened for other forms of reverse searches involving internet search terms, AI chatbot conversations, cloud storage, and video and image surveillance.

They urge the Fourth Circuit to find that the geofence warrant used in Chatrie violated the Fourth Amendment and to establish safeguards limiting the use of similar reverse searches.