NEW YORK — Luigi Mangione pleaded guilty in a Manhattan courtroom Friday to fatally stalking UnitedHealthcare CEO Brian Thompson, a dramatic turning point in the high-profile prosecution over the executive’s predawn murder outside a Midtown hotel in December 2024.

In a stunning courtroom admission before Thompson’s tearful widow, Paulette Thompson, and various family members, Mangione disclosed new details of his plot to murder the executive at a Midtown conference. He said he was able to learn details about the time and location of the event that weren’t public by contacting the company and pretending to be an investor at a major firm.

“After years of enduring severe back pain from a broken back and navigating the obstacles of the health insurance system, I learned that UnitedHealthcare would be holding its annual investor conference in New York City,” Mangione told Manhattan Federal Court Judge Margaret Garnett.

The Maryland man, a University of Pennsylvania graduate, said that he traveled to New York and emailed the company in November 2024, weeks before the conference.

“Unlike my previous interactions with insurers, I received an immediate response,” he said.

Mangione said he used a 3-D printer to make a gun equipped with a silencer, admitting that on Dec. 4, 2024, he used it to kill the executive, an Iowa native and father to two teen boys.

“I shot Mr. Thompson in Manhattan, and he died,” Mangione said.

The plea throws a wrench in Mangione’s parallel state prosecution scheduled for trial next month. Within an hour of the conference ending, his legal team filed a motion in state court seeking the dismissal of those charges on double jeopardy grounds.

“With today’s guilty plea, Mr. Mangione has accepted full responsibility for the death of Brian Thompson arising from the events of December 4, 2024,” Mangione’s lead attorney, Karen Friedman Agnifilo, said outside court after the hearing. “It was a single tragic event, yet he is being prosecuted twice for the same conduct.”

While the Manhattan U.S. attorney’s office plans to seek the maximum of life behind bars, the eleventh-hour plea could reduce Mangione’s overall exposure to prison time if he successfully uses it to get the state case thrown out. A second conviction in the state case on second-degree murder charges could result in a consecutive life sentence, all but ensuring he would die in prison.

“There are no accommodations or concessions, and we are free to seek the maximum penalty under the law,” Manhattan U.S. Attorney Jamie McDonald said outside the courthouse. “The results achieved today now allow our office to seek the maximum penalty allowed — life imprisonment.”

Garnett, who scheduled Mangione’s sentencing for Dec. 18, shortly after Thompson’s second anniversary, advised Mangione during the plea hearing that he would not be permitted to revoke his plea in the federal case if he was unhappy with the term imposed. Mangione affirmed that he understood.

“The total maximum term for both of these crimes is life in prison,” Garnett said, later notifying him of the possibility of consecutive sentences if he’s tried and found guilty in the state case.

A spokesman for Manhattan District Attorney Alvin Bragg, whose office is trying the state case, said the state plans to press forward.

“The Manhattan D.A.’s Office has been tirelessly preparing to pursue a trial conviction in New York State Supreme Court for the alleged cold-blooded murder of Brian Thompson. We are encouraged that Mr. Thompson’s family received a measure of accountability today,” Doug Cohen said. “While federal sentencing is pending, we are prepared to litigate the defense motions.”

Members of Thompson’s family attended Friday’s hearing. In a statement to the New York Daily News, they said the plea brought a measure of closure.

“Today’s guilty plea marks an important step toward justice for Brian and for our family,” the statement read. “While nothing will ease the pain of losing him, we are grateful that the federal justice system has held the person responsible for this heinous act accountable. Now we look to the court to ensure that sentencing reflects the severity of this crime. We remain mindful that additional proceedings in New York and Pennsylvania are still to come, and we will continue to seek the justice Brian deserves.”

Wearing beige prison garb, Mangione was brought into the courtroom shackled at the ankles at around 11:10 a.m. Friday, stopping for a moment to scan faces in the gallery before taking his seat at the defense table.

In contrast to his usually upbeat demeanor, Mangione appeared tired. He indicated to the judge at one point that he’d recently had trouble sleeping, taking a sleeping pill two days ago, which he affirmed had not affected his judgment in deciding to plead out.

The killing of Thompson, 50, touched off a broad debate about unaffordability in the U.S. health insurance industry, with dozens of members of the public flocking to his hearings in support of his defense. Several of his most ardent supporters who attended Friday’s hearing were seen weeping in the courtroom benches.

Abril Rios, 27, one of the self-described “Mangionistas,” said she was not shocked by the plea, and that it did not change her stance.

“I don’t think it’s shocking for me to hear. I’ve always said that I support him either way, and I’ve always felt that this could be on the table,” Rios said. “I see what happened on December 4 as an act of revolutionary protest.”

The feds’ case alleged that Mangione had stalked the executive for weeks and laid out plans to kill him in a manifesto that lamented greed in the health insurance industry at the expense of everyday Americans’ well-being. Shell casings recovered at the scene bore the words “delay,” “deny” and “defend,” apparently in reference to health insurers’ practice of routinely denying claims to maximize profits. The gunman fled the scene, and Mangione was arrested five days later at a McDonald's in Altoona, Pennsylvania.

NYPD Commissioner Jessica Tisch said her thoughts were with the victim’s family and that she applauded the NYPD and its use of “sophisticated technology” paired with “painstaking, old-fashioned detective work” to help track down Mangione in late 2024 following a nationwide manhunt.

In court, Assistant U.S. Attorney Dominic Gentile detailed extensive evidence to Garnett that prosecutors had been prepared to present at the federal trial, which was scheduled to begin in January.

Mangione was not charged with murdering Thompson in the federal case, with Garnett earlier this year dismissing the top count of murder through the use of a firearm as the other charges in the indictment did not sufficiently support it.

He is charged with Thompson’s murder under New York state law in the state case being tried by Bragg’s office, which first filed charges in relation to the Midtown killing. The trial in that case is scheduled to begin with jury selection on Sept. 8. Mangione has pleaded not guilty.

The young man has personally decried the dueling prosecutions, yelling out to courtroom spectators at a hearing earlier this year: “It’s the same trial twice. One plus one is two. Double jeopardy by any commonsense definition.”

Under New York law, a person cannot be tried twice for the same conduct, barring limited exceptions, including distinctive elements of the separate charges intended to address very different types of “harm or evil.”

Mangione, 28, has been incarcerated at the Metropolitan Detention Center in Brooklyn since his 2024 arrest.

_____

_____

©2026 New York Daily News. Visit at nydailynews.com. Distributed by Tribune Content Agency, LLC.