WILLIAM BRANGHAM: Welcome to the "News Hour."

In a surprise turn, Luigi Mangione pleaded guilty today in the shooting death of UnitedHealthcare CEO Brian Thompson.

Mangione admitted he stalked and shot Thompson in 2024 outside the Hilton Hotel in Manhattan.

He potentially faces life in prison.

The 28-year-old is also still facing murder charges for Thompson's death in New York state.

Our justice correspondent, Ali Rogin, is here with more.

Ali, so this is a somewhat surprised turn in this horrendous murder that got so much attention nationally.

Walk us through what happened in court today.

ALI ROGIN: William, we heard from Luigi Mangione today say for the first time in a short, but chilling statement -- quote -- "I shot Mr.

Thompson and he died.

I knew that what I was doing was illegal."

He expressed no contrition, no remorse.

And even though, William, there were no cameras in the courtroom, reporters in the room really conveyed this palpable sense of drama and tension.

The family of the late Brian Thompson was sitting in the front row, and they reportedly began crying as Mangione detailed some of the planning and execution of this crime.

WILLIAM BRANGHAM: There was so much evidence against Mangione, the video of the shooting, the weapon, his diary that laid out some of this plot.

But do we know, was that the principal reason why he made this plea?

What else did we learn?

ALI ROGIN: It may have been to avoid trial, but it was clearly also setting up, hopefully for him and his defense team, a cancellation of a state case that is also being -- proceeding at the same time.

He pleaded guilty today.

There were two counts of stalking resulting in the death of Brian Thompson.

But it wasn't a murder charge, because, in federal court, murder charges are very, very rare and specific.

But he is charged with murder in that second concurrent case, which is playing out on the state level in New York.

His defense has long maintained that these two cases proceeding at the same time represents double jeopardy, violating the constitutional protection against being tried twice for the same crime.

And New York's state law's double jeopardy restrictions are even stricter.

They say a defendant cannot be separately prosecuted for two offenses arising from the same action.

So, in this case, that would be the killing of Brian Thompson.

Mangione's defense argues that, now that he's pleaded guilty to the federal offense, he cannot under New York state law be prosecuted for state offenses arising from that state crime.

The state trial is scheduled to begin in early September, but, today, Mangione's defense filed a motion to have it dismissed.

WILLIAM BRANGHAM: Did we learn anything else about this notorious case?

ALI ROGIN: We did.

He detailed some of his planning leading up to the murder.

He said that he was motivated by years of back pain and what he believed was a health insurance system working against him.

He said that, once he learned that the UnitedHealthcare Company was holding an investor summit in Manhattan, he e-mailed company leadership posing as an investor to get information about where and when this meeting was taking place.

And that's how he was able to confront Brian Thompson.

Mangione also shared an observation with the judge that had clearly made an impression on him.

He talked about how, while he was posing as a wealthy investor, leadership e-mailed him back within an hour, and he said that was in stark contrast to his interactions with insurers as a patient.

WILLIAM BRANGHAM: Ali Rogin, thank you so much.

ALI ROGIN: You bet.