A Pennsylvania police officer testified that Luigi Mangione calmly warned him about items in his pockets just before his arrest in connection with the killing of UnitedHealthcare CEO Brian Thompson.
Officer Stephen Fox of the Altoona Police Department told jurors in Manhattan Supreme Court on Tuesday, Dec. 9 — exactly one year after Mangione’s arrest — that Mangione made two notable statements as Fox frisked him.
“He told me he had a jar of peanut butter in his coat pocket,” Fox testified.
“He told me he had a knife in his right pants pocket.”
Fox encountered Mangione at a McDonald’s on East Plank Road in Altoona, where Mangione was being detained after allegedly presenting a fake ID bearing the name Mark Rosario.
Unlike some of the other arresting officers who have taken the stand during five days of lengthy evidence suppression hearings, Fox appeared deeply familiar with the broader case. He testified that he viewed the killing as a “violent act of cowardice” and believed it to be a “clear targeted assassination of an individual in the hierarchy of healthcare.”
Fox and fellow officer Christy Wasser were tasked with searching Mangione’s large black backpack at the McDonald’s. According to police body camera footage played in court, the officers discovered a fully loaded magazine wrapped in a pair of wet underwear inside the bag. In the footage, Fox can be heard reacting: “It’s f—ing him, 100%.”
Both Fox and Wasser testified that they were concerned the backpack might contain an explosive device, which is why they wanted to search it at the restaurant instead of transporting it elsewhere.
“You don’t want to blow Blue up,” Fox said in the footage, referring to his K9 partner. “You can blow me up.”
That on-the-spot search has become a central issue in the suppression hearings. Mangione’s attorneys argue the backpack was searched illegally and without a warrant. Prosecutors and Altoona police maintain the search was lawful as an action “incident” to Mangione’s arrest on forgery-related suspicion — though body camera footage captured at least one officer questioning whether a warrant was required.
Authorities say that once the backpack was taken back to the station, officers allegedly found a handgun, a silencer and a notebook described as a “manifesto” expressing a desire to “wack” a health insurance CEO.
Defense attorneys have also focused on the brief transfer of the backpack between the McDonald’s and the police station — a moment not captured on any body camera. Fox testified that the handoff between himself and Wasser, after he was called back to the restaurant, lasted only about 10–12 seconds. However, defense lawyer Karen Friedman Agnifilo suggested on Monday that the pair might have secretly searched the bag during that time, discovered the gun then, or even planted it. Fox rejected that implication.
Fox further testified that he later helped transport Mangione to the Blair County Courthouse for his arraignment, where they were met by a large media presence amid intense public interest in the case. As they walked, Fox recalled Mangione turning to him and saying, “All these people here for a mass murderer, why?”
Mangione then stumbled because his legs were shackled and Fox was walking too quickly, the officer said. Fox testified that he apologized, and Mangione responded, “It’s okay, I’m going to have to get used to it.”
During cross-examination, Agnifilo challenged Fox over how and when he delivered Mangione’s Miranda warnings, suggesting he did so prematurely in hopes of eliciting statements before Mangione was formally under arrest. Fox denied that characterization.
Mangione has pleaded not guilty to murder charges in both state and federal court, as well as to forgery charges in Pennsylvania. He is currently being held pretrial at the Metropolitan Detention Center in Brooklyn and is expected to face trial in 2026.
Earlier testimony in the hearings has come from additional Altoona officers involved in Mangione’s arrest and interrogation, along with two prison guards who said they spoke with him while he was in solitary confinement.
