Luigi Mangione, accused of gunning down an insurance executive in cold blood in a slaying that has divided Americans, pleaded not guilty to murder charges Friday, after he was arraigned in court.
Mangione has now been charged in both New York state and federal court over the killing of UnitedHealthcare CEO Brian Thompson. He pleaded not guilty to the federal charges in a Manhattan court on Friday.
The case has stirred debate about political violence and the state of the healthcare system in the United States, and is the first case in which the Justice Department is seeking the death penalty since Donald Trump returned to the White House.
Mangione wore beige prison scrubs -- in contrast with the sharp, civilian wardrobe in which he has previously appeared -- and conferred with his lawyers, an AFP correspondent saw.
He is charged with murder, two counts of stalking, and a firearms offense.
The focus in the case will now shift to the trial date, with the judge due to set a timetable at a hearing scheduled on December 5, exactly a year and a day after last year's murder.
Outside court, a van fitted with a video screen accused the Justice Department of "barbaric" conduct alongside an image of Mangione.
Well-wishers brandished signs and chanted, with one stopping to admonish prosecutors for rushing the cases against him.
One woman dressed in the green overalls of the Super Mario character Luigi and brandished a sign relating to the case.
Lindsay Floyd, an activist working in support of Mangione, said ahead of the hearing that "these are serious accusations that deserve some reflection, not this vilification before the trial has even begun."
Early on December 4, 2024, Mangione allegedly tracked Thompson in New York, walked up behind him and fired several gunshots from a pistol with a silencer, federal prosecutors said.
He had traveled to the city by bus from Atlanta about 10 days before the crime.
Mangione was arrested in Altoona, Pennsylvania, on December 9, following a tip from staff at a McDonald's restaurant after a days-long manhunt.
In the state case, Mangione has also pleaded not guilty and could face life imprisonment with no parole, if convicted.
Mangione's lawyer Karen Agnifilo -- wife of Sean "Diddy" Combs's lawyer Marc Agnifilo -- said that the federal case should be heard before the state one because of the risk of the death penalty.
Marc Agnifilo was seen rushing from a hearing in the Combs case to attend the arraignment of Mangione, for whom he is also a lawyer.
"It's a side door kind of day," he said.
Elliott Gorn, a history professor at Loyola University Chicago, said that what struck him most in the days following the murder "was the deep sense of grievance that many Americans were suddenly talking about in the open."
"We'd just had a months-long political campaign, and the subject barely came up, but then suddenly the floodgates opened, and everyone seemed to have a horror story of medical care denied," he said.