(NEW YORK) — One year after prosecutors say Luigi Mangione brazenly assassinated UnitedHealthcare CEO Brian Thompson in midtown Manhattan, the 27-year-old is due in court for a multi-day hearing that could determine the balance of evidence in his state murder trial.

Mangione’s attorneys are trying to limit prosecutors from using key evidence — including a 3D-printed gun and purported journal writings — police say they obtained when they arrested him in Pennsylvania last year. 

Though no trial date has been set for either Mangione’s state or federal criminal cases, the outcome of this week’s hearing will determine the shape of the case Mangione and his lawyers will face at trial.  If they succeed in limiting key evidence, prosecutors could lose the ability to use Mangione’s writings — which prosecutors say paint a clear motive for the crime — and the alleged murder weapon. 

“I finally feel confident about what I will do,” Mangione allegedly wrote in a notebook seized from his backpack, later included in court filings. “The target is insurance. It checks every box.”

This week’s hearing in New York’s State Supreme Court — where Mangione is charged with second-degree murder — follows a legal victory for Mangione’s defense when the judge in September tossed two murder charges related to an act of terrorism. He is still charged with second-degree murder and other offenses, as well as a separate criminal case in federal court. If convicted in state court, Mangione faces a potential life sentence, and he could face the death penalty in his federal case. 

Mangione is accused of gunning down Thompson — a father of two who spent two decades working for UnitedHealthcare before being named its CEO — last December outside a Midtown Manhattan hotel before allegedly fleeing the city. He was arrested five days later in a McDonald’s in Altoona, Pennsylvania, after someone reported seeing a “suspicious male that looked like the shooter from New York City.” 

Mangione’s arrest is expected to be at the center of this week’s hearing, with defense lawyers arguing that police extensively questioned him without reading him his rights and searched his backpack without a warrant.

Defense lawyers are trying to bar prosecutors from using any of the evidence recovered from the backpack — including electronic devices, a 3D-printed gun, silencer, and a journal — as well as referencing any statements Mangione made to police. Lawyers with the Manhattan District Attorney’s Office have defended the lawfulness of the arrest and search and are expected to argue that the evidence would have inevitably been recovered during the discovery process ahead of trial.

“Despite the gravest of consequences for Mr. Mangione, law enforcement has methodically and purposefully trampled his constitutional rights,” Mangione’s attorney argued in their motion. 

Defense lawyers argue the constitutional issues began almost immediately after officers approached Mangione, who was seated in the McDonald’s to have breakfast. After Mangione allegedly provided officers with a fake driver’s license, they immediately began questioning Mangione about whether he was recently in New York and why he lied about his identity, defense lawyers say. As he was questioned, defense lawyers say officers filled the restaurant to form an “armed human wall trapping Mr. Mangione at the back of the restaurant.”  

Citing time-stamped police body camera footage, Mangione’s attorneys allege police waited 20 minutes to read his Miranda Rights and extensively questioned him without informing him he was under investigation or that he had the right to remain silent. They have asked New York State Supreme Court Judge Gregory Carro to prohibit prosecutors from introducing any evidence or testimony related to what they say was an illegal interrogation at the McDonald’s. 

Defense lawyers also contend that an officer illegally searched Mangione’s bag while he was being interrogated, eventually discovering a loaded magazine and handgun. Despite another officer commenting, “at this point we probably need a search warrant” for the bag, Mangione’s attorneys argue that the officer continued searching the bag and claimed she was trying to make sure there “wasn’t a bomb or anything” in the bag. 

“[The officer] did not search the bag because she reasonably thought there might be a bomb, but rather this was an excuse designed to cover up an illegal warrantless search of the backpack,” they argue. “This made-up bomb claim further shows that even she believed at the time that there were constitutional issues with her search, forcing her to attempt to salvage this debacle by making this spurious claim.” 

Mangione’s attorneys argue that any of the items recovered from the backpack, including his alleged writings and weapon, should be limited as “fruit” of an illegal search. 

Ahead of the hearing, Mangione’s attorneys have previewed plans to call at least two witnesses from the Altoona Police Department. During an unrelated court hearing last week, one of Mangione’s attorneys claimed that the hearing could include more than two dozen witnesses and hours of body camera footage. 

Judge Carro has set aside several days beginning Monday to hear arguments about whether the testimony and evidence can be suppressed.

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