Luigi Mangione pleaded guilty on Friday to federal stalking charges in the 2024 killing of UnitedHealthcare CEO Brian Thompson.

Mangione, 28, entered the plea at a hastily scheduled hearing in Manhattan federal court, resolving one of two cases against him in connection with Thompson’s death. With this guilty plea, his lawyers could seek to have the state case thrown out on double jeopardy grounds.

Mangione was charged by both federal and state prosecutors with ambushing Thompson, 50, outside a New York City hotel on Dec. 4, 2024, as the insurance executive walked to his company’s annual investor conference.

Surveillance video of the killing showed a masked gunman shooting Thompson from behind. Police say “delay,” “deny” and “depose” were written on the ammunition, mimicking a phrase used to describe how insurers avoid paying claims. That detail — and revelations that Mangione’s private writings lambasted health insurers as greedy, according to authorities — made the case a fulcrum for debate about the industry and made Mangione a cause célèbre for some of its critics.

Mangione never was a UnitedHealthcare customer, according to police and the company. A University of Pennsylvania graduate from a wealthy Maryland family, he was arrested five days after the shooting, when he was spotted at a McDonald’s in Altoona, Pennsylvania. It’s about 230 miles (370 kilometers) west of Manhattan.

Thompson led one of the United States’ largest health insurers, but he wasn’t well known outside the industry. Trained as an accountant, he had worked at parent company UnitedHealth Group Inc. for 20 years and became CEO of its insurance arm, UnitedHealthcare, in 2021.

A trial on state murder charges is scheduled to start next month. It is unclear whether that trial would go forward if Mangione pleaded guilty in the federal case.

The federal charges accuse Mangione of stalking Thompson to cause his death. Both the federal and state cases could lead to a life prison sentence. A federal judge earlier this year tossed out additional charges that could have exposed Mangione to a potential death penalty.

Mangione had complained about the prospect of two trials, telling a judge in February: “It’s the same trial twice. One plus one is two. Double jeopardy by any commonsense definition.”

Under New York law, a state prosecution could potentially be barred if the federal case is resolved first.

The state’s double jeopardy protections kick in if a jury has been sworn in a prior prosecution, such as a federal case, or if that prosecution ends in a guilty plea. Mangione’s cases involve different charges arising from the same course of conduct.

In a letter last month, state prosecutors objected to the possibility of a guilty plea in the federal case wiping out the state case.

U.S. District Judge Margaret M. Garnett has delivered some setbacks to the defense, including ruling in January that prosecutors could use items collected from Mangione’s backpack during his arrest as evidence against him.

They included a 3D-printed pistol that investigators said matched the one used to kill Thompson and a notebook in which authorities say Mangione described his intent to kill an insurance executive.

In June, Mangione’s lawyers said they would pursue a psychiatric defense in the state case but reversed course a day later. The defense, involving claims that he was suffering from extreme emotional disturbance at the time of the killing, isn’t allowed in federal court.

(AP)