A banner displays a picture of Luigi Mangione, the suspect in the killing of UnitedHealthcare chief executive Brian Thompson, outside Manhattan Criminal Court, ahead of his appearance for a pre-trial hearing on murder charges, in New York City, New York, U.S., December 1, 2025. REUTERS/Mike Segar
Luigi Mangione, 26, a suspect in the New York City killing of UnitedHealth executive Brian Thompson, poses for a booking photograph in Altoona, Pennsylvania, U.S. December 10, 2024 in a combination of photographs. Altoona Police Department/Handout via REUTERS
Supporters of Luigi Mangione, the suspect in the killing of UnitedHealthcare chief executive Brian Thompson, gather outside Manhattan Criminal Court, ahead of his appearance for a pre-trial hearing on murder charges, in New York City, New York, U.S., December 1, 2025. REUTERS/Mike Segar
A supporter of Luigi Mangione, the suspect in the killing of UnitedHealthcare chief executive Brian Thompson, holds a sign outside Manhattan Criminal Court, ahead of his appearance for a pre-trial hearing on murder charges, in New York City, New York, U.S., December 1, 2025. REUTERS/Mike Segar

By Jack Queen

NEW YORK, Dec 1 (Reuters) - Luigi Mangione, the man accused of gunning down a UnitedHealthcare executive outside a Manhattan hotel, is due in state court on Monday for a series of high-stakes hearings on the admissibility of key pieces of evidence at his murder trial.

Mangione, 27, was arrested in December 2024 and charged with fatally shooting UnitedHealthcare CEO Brian Thompson on a sidewalk in Midtown Manhattan. Public officials condemned the shocking assassination. Mangione became a folk hero to some Americans who decry steep healthcare costs.

He has pleaded not guilty to murder and other charges and is expected to face trial next year. Mangione has pleaded not guilty in a separate federal case where prosecutors plan to seek the death penalty.

Several supporters of Mangione appeared outside the courthouse, including one dressed as the villain from the video game Super Mario Bros and bearing a sign that said, "When patients die, profits rise."

The hearings before Judge Gregory Carro could last the entire week and feature testimony from witnesses involved in Mangione’s arrest in Pennsylvania, where Mangione’s lawyers say he was illegally searched and questioned.

The defense lawyers are seeking to block prosecutors from presenting evidence police say was found in Mangione’s backpack, including a 3D-printed gun, silencer, electronic devices and journal writings that appear to implicate him in the killing.

Mangione’s lawyers are also seeking to suppress statements he gave to police during his arrest, saying police did not give Mangione proper notice of his legal rights.

Prosecutors with the office of Manhattan District Attorney Alvin Bragg have opposed Mangione’s requests to suppress the evidence and denied his claims that he was illegally searched and questioned.

Mangione could face life in prison if convicted of murder in the second degree, which is defined as an intentional killing. He also faces seven counts of criminal possession of a weapon and one count of possessing a false identification.

Carro dismissed two terrorism counts against Mangione in September, finding prosecutors had not presented enough evidence that Mangione intended to intimidate health insurance workers or influence government policy.

Trial dates have not yet been set in either the state or federal cases. Mangione has been held in federal custody in Brooklyn since his arrest.

(Reporting by Jack Queen in New York; Editing by Alistair Bell and Lisa Shumaker)