The videos, including footage from the restaurant previously unseen by the press or the public, kicked off a hearing on Mangione’s fight to bar evidence from his state murder trial, including the gun prosecutors say matches the one used in the Dec. 4, 2024, attack. Thompson was killed as he walked to a Manhattan hotel for his company’s annual investor conference.

Mangione, 27, pressed a finger to his lips and a thumb to his chin as he watched footage of two police officers approaching him as he ate breakfast at the McDonald’s in Altoona, Pennsylvania, about 230 miles (about 370 kilometers) west of Manhattan.

He gripped a pen in his right hand, making a fist at times, as prosecutors played a 911 call from a McDonald’s manager relaying concerns from customers that Mangione looked like the suspect in Thompson’s killing. The manager said she searched online for photos of the suspect and that as Mangione sat in the restaurant, she could only see his eyebrows because he was wearing a beanie and a medical face mask.

Among the evidence Mangione’s defense team wants excluded are the 9 mm handgun and a notebook in which prosecutors say he described his intent to “wack” a health insurance executive. Both were found in a backpack Mangione had with him when he was arrested.

Mangione, the Ivy League-educated scion of a wealthy Maryland family, has pleaded not guilty to state and federal murder charges. The state charges carry the possibility of life in prison, while federal prosecutors are seeking the death penalty. Neither trial has been scheduled yet. The next hearing in the federal case is scheduled for Jan. 9.

Defense wants to bar the gun and notebook from his trial

After getting state terrorism charges thrown out in September, Mangione’s lawyers are zeroing in on what they say was unconstitutional police conduct that threatens his right to a fair trial.

They contend that the Manhattan district attorney’s office should be prevented from showing the gun, notebook and other items to jurors because police didn’t have a search warrant.

They also want to suppress some of Mangione’s statements to police, such as when he allegedly gave his name as Mark Rosario, because officers started asking questions before telling him he had a right to remain silent. Prosecutors say Mangione gave the same name when he checked into a Manhattan hostel days before the killing.

Surveillance video showed a masked gunman shooting Thompson from behind. Prosecutors say “delay,” “deny” and “depose” were written on the ammunition, mimicking a phrase used to describe how insurers avoid paying claims.

Eliminating the gun and notebook would be critical wins for Mangione’s defense and a major setback for prosecutors, depriving them a possible murder weapon and evidence they say points to motive. Prosecutors have quoted extensively from Mangione’s writings in court filings, including his praise for the late Theodore Kaczynski, the convicted murderer known as the “Unabomber.”

Among other things, prosecutors say, Mangione mused in his diary about rebelling against “the deadly, greed fueled health insurance cartel” and wrote that killing an industry executive “conveys a greedy bastard that had it coming.”

An officer searching the backpack found with Mangione was heard in body camera footage saying she was checking to make sure there “wasn’t a bomb” in the bag. His lawyers argue that was an excuse “designed to cover up an illegal warrantless search of the backpack.”

Laws concerning how police interact with potential suspects before reading them their rights or obtaining search warrants are complex and often disputed in criminal cases.

Federal prosecutors, fighting a similar defense effort in that case, have said in court filings that police were justified in searching the backpack to make sure there were no dangerous items, and that his statements to officers were voluntary and were made before he was under arrest.

Pivotal pretrial hearing could last more than a week

Court officials say the hearing could last more than a week, meaning it would extend through Thursday’s anniversary of the killing. Defense lawyer Marc Agnifilo told a judge in an unrelated matter last week that Manhattan prosecutors had indicated they could call more than two dozen witnesses.

Mangione was allowed to wear normal clothing to court instead of a jail uniform. He entered the courtroom Monday in a gray suit and a button-down shirt with a checkered or tattersall pattern. Court officers removed his handcuffs to allow him to take notes.

The prosecution’s first witness, Sgt. Chris McLaughlin of the New York Police Department’s public affairs office, testified about efforts to disseminate surveillance images of the suspect to news outlets and on social media in the hours and days after the shooting.

To illustrate the breadth of news coverage during the five-day search for the shooter, prosecutors played a surveillance video of the shooting that aired on Fox News Digital, footage from the network of police divers searching a pond in Central Park and clips from the network that included images of the suspected shooter that were distributed by police.

Bernard Pyles, an installation supervisor who helped maintain the surveillance camera system at the McDonald’s, also testified Monday. He downloaded video clips for police after Mangione’s arrest.

A few dozen Mangione supporters watched the hearing from the back of the courtroom. One wore a green T-shirt that said: “Without a warrant, it’s not a search, it’s a violation.” Another woman held a doll of the Luigi video game character and had a smaller figurine of him clipped to her purse.