Luigi Mangione, the man accused of killing UnitedHealthcare CEO Brian Thompson, appeared in state court on Monday, Dec. 1, as his attorneys attempt to get key pieces of evidence tossed out of his New York murder case.

Mangione, 27, was arrested nearly a year ago at a McDonald's in Altoona, Pennsylvania, after authorities say he fatally shot Thompson outside a Midtown Manhattan hotel in New York City on Dec. 4, 2024.

In hearings this week, Mangione's defense attorneys will battle prosecutors over evidence police recovered in Mangione's backpack at the time of his arrest, including a notebook, a silencer and a 3D-printed handgun that prosecutors say connect Mangione to the killing.

Mangione's attorneys argue that police searched the backpack before obtaining a warrant and, therefore, the evidence should be excluded from trial. The defense is also seeking to toss out statements made by Mangione during his arrest, arguing that police questioned him before reading him his Miranda rights.

Manhattan prosecutors have rejected the defense's claims that Mangione was illegally searched and questioned.

The outcome of the hearings will be consequential, as it will determine whether a jury will hear about a gun purportedly linked to the murder scene and writings that describe an intent to "wack" a health care executive.

On the first day of the hearings, Mangione wore a gray suit and a button-down shirt with a checkered pattern. Unshackled, he took notes and could be seen speaking with his attorneys. Judge Gregory Carro had earlier granted Mangione's request to wear civilian clothes in court.

Outside, several people held signs reading "FREE LUIGI" and chanted in defense of the Ivy League graduate. Such demonstrations have been a fixture of Mangione's hearings since his arrest last year.

In his New York state case, Mangione faces nine felony counts, including second-degree murder, which carries a possible sentence of 25 years to life in prison. In September, Carro dismissed terrorism-related charges against Mangione, stating that prosecutors did not present enough evidence to warrant them.

Mangione separately faces a federal death penalty prosecution, as well as several charges in Pennsylvania. He has pleaded not guilty to all the charges.

The hearings in New York state court are expected to last several days as prosecutors and defense attorneys present arguments over the evidence and statements Mangione made during an initial interrogation.

What evidence is Mangione trying to get thrown out?

The Manhattan District Attorney's Office previously highlighted the writings that police say they recovered from Mangione's backpack, arguing that they show how he allegedly plotted the attack.

"The target is insurance. It checks every box," the notebook says, according to court filings submitted by New York prosecutors.

Along with the writings, police also found a ghost gun that authorities say match shell casings recovered from the scene where Thompson was killed.

Mangione's attorneys have also moved to exclude statements made by Mangione during his arrest, including a fake name he allegedly gave police.

Other evidence against Mangione include items found near the crime scene that authorities say contained his DNA, including a cell phone and a water bottle.

Trial dates have not been set in either of Mangione's state or federal cases.

(This story has been updated to add new information.)

Contributing: Reuters; Karissa Waddick, USA TODAY

This article originally appeared on USA TODAY: Luigi Mangione back in court as attorneys seek to exclude key evidence

Reporting by Christopher Cann, USA TODAY / USA TODAY

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