Murder suspect Luigi Mangione exuded confidence as he punched the air with a smile during his court appearance this morning.

At 27, Mangione chose a grey suit paired with a blue shirt for his Manhattan Criminal Court appearance, opting out of wearing a tie for the suppression of evidence hearing on Monday.

His defense team is working to prevent the use of a gun, notebook, and other items that law enforcement claims were discovered in his backpack during his arrest at a McDonald’s in Altoona, Pennsylvania, last December.

Additionally, Mangione and his attorneys are attempting to block certain statements he allegedly made to the police.

His arrest occurred five days following the fatal shooting of UnitedHealthcare CEO Brian Thompson on a New York City sidewalk.

Thompson, 50, was shot from behind as he walked to an investor conference. He became UnitedHealthcare’s CEO in 2021 and had worked within parent UnitedHealth Group Inc. for 20 years.

Mangione has pleaded not guilty to state and federal murder charges. Monday’s evidentiary hearing applies only to the state case.

The state charges carry the possibility of life in prison, while federal prosecutors are seeking the death penalty. Neither trial has been scheduled.

Murder suspect Luigi Mangione was seen pumping his fist as he gleamed in Manhattan Criminal Court on Monday morning

Mangione  appears in Manhattan Supreme Court alongside his attorney Karen Friedman Agnifilo during an evidentiary hearing on Monday

Mangione’s lawyers want to keep jurors at both eventual trials from hearing about his alleged statements to law enforcement and about items authorities said they seized from his backpack. 

The objects include a 9 mm handgun that prosecutors say matches the one used in the killing and a notebook in which they say Mangione described his intent to ‘wack’ a health insurance executive.

Prosecutors have claimed that Mangione gave police a fake ID, which he had earlier used when he checked into a New York City hostel ahead of the shooting.

After apparently determining that the license was fake, responding officers then called in the name Luigi Mangione and a birthdate.

But Mangione’s attorneys are trying to bar that evidence from being heard at his upcoming trial, claiming that officers started asking their client questions before telling him he had a right to remain silent.

Mangione’s attorneys argue the backpack items should be excluded because police didn’t get a warrant before searching his bag.

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

In Mangione’s case, crucial questions will include whether he believed he was free to leave at the point when he spoke to the arresting officers, and whether there were ‘exigent circumstances’ that merited searching his backpack before getting a warrant.

Prosecutors allege Mangione is the suspect who was caught on surveillance footage shooting Thompson at point-blank range on December 4, 2024

Mangione’s defense is seeking to bar admission of items found in his backpack when he was arrested at a McDonald’s in Altoona, Pennsylvania, because cops didn’t have a warrant – including a 3D printed gun and silencer (pictured) allegedly used in Thompson’s shooting 

A handwritten note depicts a to-do list for the dates December 8 and 9, mentioning a trip to Best Buy, as well as ‘survival kit.’ It was found on Mangione during his arrest

Officer Joseph Detwiler testified that he neither told Mangione he couldn’t leave nor mentioned the New York shooting. 

Defense lawyers, however, have argued that officers ‘strategically’ stood in a way that prevented him from leaving even before he was told he was being arrested.

As for the backpack search, Detwiler said Altoona police policy calls for searching anyone who is being arrested, including their bags. 

Manhattan prosecutors haven’t yet laid out their arguments for allowing the disputed evidence. 

Their federal counterparts have said in court filings that police were justified in searching the backpack to ensure there were no dangerous items and that Mangione’s statements to officers were voluntary and made before he was under arrest.

Surveillance video showed a masked gunman shooting Thompson from behind as the executive walked to a midtown Manhattan hotel for his company’s annual investor conference. 

Prosecutors say ‘delay,’ ‘deny’ and ‘depose’ were written on the ammunition, mimicking a phrase critics use to describe insurance industry practices.

State Supreme Court Justice Gregory Carro will hear from more than 20 witnesses before he makes a ruling on the admissibility of the evidence. 

Luigi Mangione was taken into custody at the McDonald’s in Altoona, Pennsylvania last year

A fake ID registered to New Jersey under the name Mark Rosario was found on Mangione when he was arrested last December 

The crime and Mangione’s ensuing arrest led him to become somewhat of a celebrity, with his fans saying that he had taken a ‘bite out of corruption.’

Fans  appeared en masse as the alleged assassin appeared in court on last week.

Many were wearing a selection of merchandise supporting the alleged killer and vying for his attention.