Mangione, 28, entered the plea at a hastily scheduled hearing in Manhattan federal court. “On the morning of Dec. 4, 2024, I shot Mr. Thompson in Manhattan, and he died,” Mangione told the court.

He admitted to emailing UnitedHealthcare ahead of time and posing as a potential investor, using the ruse to confirm the location of the company’s investor conference so he could track Thompson’s whereabouts. Mangione was never a customer of UnitedHealthcare, according to both police and the company.

U.S. Attorney Jamie McDonald told reporters at a post-hearing press conference that it was an open plea and there was no deal with the defense. Now, there’s a question of whether the state can continue its murder trial, scheduled to begin next month. Today’s federal plea does not automatically wipe out the state’s murder trial.

“Mr. Mangione has accepted full responsibility for the death of Brian Thompson,” his lawyer Karen Friedman Agnifilo told reporters outside court, arguing that her client shouldn’t face two prosecutions over a “single tragic event.”

Mangione pleaded guilty to all pending counts in the indictment with no agreement in place, meaning prosecutors face no restrictions on the sentence they can pursue. McDonald said Mangione “pled open,” receiving no concessions, and that the government is free to seek the maximum penalty under the law.

Before accepting the plea, U.S. District Judge Margaret M. Garnett asked Mangione a series of questions and found him to be “fully competent” after he said he felt his mind was clear. Mangione is set to be sentenced Dec. 18, and faces a maximum of life in prison.

The state case now hangs in the balance

Within hours of the plea, Mangione’s defense filed a motion to dismiss the separate New York murder and weapons charges against him. His attorney argued the dual prosecutions arising from the same event violated Mangione’s rights, and the motion alleges the Manhattan District Attorney’s Office and the Justice Department coordinated to schedule the state case ahead of the federal one specifically to sidestep double jeopardy protections. The motion also claims both sets of prosecutors overcharged him.

The Manhattan DA’s office said the office is prepared to litigate the defense motions and has been preparing since December 2024 to pursue a conviction in state supreme court.

Mangione was arrested five days after the Dec. 4, 2024 shooting at a McDonald’s in Altoona, Pennsylvania, about 230 miles west of Manhattan. Prosecutors say ammunition at the scene was inscribed with “delay,” “deny” and “depose,” echoing language used to describe how insurers deny claims. The words helped turn the case into a flashpoint over the health insurance industry, drawing a cult following to his hearings.

A federal judge dismissed additional charges against Mangione earlier this year, including one that could have exposed him to the death penalty. His lawyers have also fought in pretrial hearings to suppress evidence seized from his backpack, including a notebook and to-do list prosecutors say detailed his intent to kill an insurance executive, arguing in an earlier filing that he wasn’t read his rights and that the backpack search was warrantless. In June, his lawyers briefly said they would pursue a psychiatric defense in the state case, centered on claims he was suffering from extreme emotional disturbance at the time of the killing, all before reversing course a day later. That defense isn’t available in federal court.