A federal judge will hold a brief hearing in the coming weeks to examine the procedures used by police when they seized and searched Luigi Mangione's backpack following his arrest in the killing of UnitedHealthcare CEO Brian Thompson.

US District Judge Margaret Garnett said the hearing would be limited to a single witness -- an Altoona, Pennsylvania, police officer with “sufficient authority and experience” to testify on the department’s established procedures for securing, safeguarding, and inventorying a person’s personal property during a public arrest. The officer does not need to have been involved in Mangione’s arrest, which occurred in December 2024. Garnett directed prosecutors to coordinate with Mangione’s attorneys on scheduling, moving the discussion earlier than the previously planned Jan. 30 conference.

Mangione, who has pleaded not guilty to federal and state murder charges that carry the possibility of life imprisonment, is challenging the legality of the backpack search. His lawyers argue that officers violated his rights by examining items - including a gun alleged to match the murder weapon and a notebook with purported threats - before obtaining a warrant. Prosecutors maintain that the search was consistent with Altoona police protocols, which require officers to promptly check a suspect’s property for dangerous items at the time of arrest. A subsequent warrant was obtained, and an inventory search at the police station cataloged the remaining contents, including the firearm, silencer, and handwritten notes.

The case highlights the complex legal debates surrounding warrant requirements and search procedures. As part of the hearing, Garnett has ordered prosecutors to submit the affidavit used to secure the federal search warrant. Mangione’s defence contends that the initial warrantless search may have influenced the affidavit, though prosecutors say it does not reference specific items found during the early search.

Legal experts say the outcome of the hearing could have implications beyond this high-profile case. A ruling clarifying what constitutes a lawful inventory or warrantless search may influence how police departments across the country conduct searches during arrests, particularly in cases involving potentially dangerous items or high-stakes criminal investigations. Evidence deemed inadmissible could prompt law enforcement agencies to adjust training, protocols, and documentation practices to ensure compliance with constitutional standards and minimize the risk of legal challenges.