The scion of a prominent Maryland family who was top of his class at an elite private school before graduating from an Ivy League university, Luigi Mangione seemed to have everything going for him, according to friends.

They were left stunned by the now-28-year-old’s fatal shooting of UnitedHealthcare’s chief executive Brian Thompson on 4 December 2024 outside of a hotel in New York City.

Mangione initially denied that he murdered the father of two and pleaded not guilty, but on 14 August he changed his plea to guilty in the federal case, admitting to two charges of interstate stalking resulting in death.

• ‘I shot Mr Thompson’- What it was like inside court as Mangione pleaded guilty
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Mangione, in a statement confessing to the court, said that he was driven to kill Thompson because of his experience with the healthcare system “after years of enduring severe pains from a broken back”.

He said he researched and found that the health executive would be at a meeting in New York City.

“I shot Mr Thompson in Manhattan and he died,” he admitted in a New York court.

Mangione was held for nearly two years without bail at a notorious jail in Brooklyn, which also holds rapper Sean “Diddy” Combs.

His sentencing in the federal case is in December. Mangione also faces state charges.

In New York, where his state trial is slated to begin in September, he faces eight charges including second-degree murder, possession of a forged instrument (for an alleged fake driver’s license), and six counts of criminal possession of a weapon.

His lawyers are seeking to get the majority of those charges dismissed following his guilty plea in the federal case. The remaining charge would be over the alleged fake ID card.

Mangione was arrested five days after the attack, at a McDonald’s in Altoona, Pennsylvania. He was allegedly in possession of a gun, bullets, multiple fake IDs and cash. Mangione also had a handwritten document that expressed “ill will” towards corporate America and included passages such as “frankly, these parasites had it coming”, according to police.

Mangione comes from a prominent family in the Baltimore area who reportedly are known for businesses including country clubs, nursing homes and a radio station.

His paternal grandparents, Nicholas and Mary Mangione, were real estate developers who purchased the Turf Valley Country Club in 1978 and Hayfields Country Club in Hunt Valley in 1986.

Shortly after Mangione was charged, his cousin, Republican state lawmaker Nino Mangione, released a statement saying the family was “shocked and devastated”.

“We offer our prayers to the family of Brian Thompson and we ask people to pray for all involved”, the statement read.

Thomas Maronick, a defence attorney who knows members of the family, told the BBC of his shock at the charges.

“You wouldn’t think someone of privilege or means from a family that’s known for doing so much for the community would do something like this,” he said.

Mangione attended the private, all-boys Gilman School in Baltimore. He was valedictorian, an accolade usually bestowed on the student with the highest academic achievements.

Speaking to the BBC’s US partner, CBS News, one of his classmates said Mangione “didn’t have any enemies” and was a “valedictorian for a reason”.

Mangione went on to graduate from the University of Pennsylvania, where he received a bachelor’s and master’s degree in computer science, according to the school, and founded a video game development club.

A friend who attended the Ivy League college at the same time as Mangione described him as a “super normal” and “smart person”.

Mangione was employed as a data engineer for TrueCar, a digital retailing website for new and used cars, according to his social media profiles. A company spokesman told the BBC he had not worked there since 2023.

He also spent time in a co-living surfing community in Hawaii called Surfbreak. Sarah Nehemiah, who knew him then, told CBS he left due to his back injury, which had worsened from surfing and hiking.

Mangione’s mother reported him missing in November to San Francisco authorities, telling them she had not heard from her son since July.

After police began investigating the shooting, the missing person report Mangione’s mother filed was flagged to authorities, according to the New York Police Department.

Police contacted Mangione’s mother, who did not identify her son as the suspect but said “it might be something that she could see him doing”.

Friends have told US media he had surgery on his back. The background image on an X account believed to belong to Mangione shows an X-ray of a spine with hardware in it.

On a Reddit account that appears to have belonged to him, Mangione reportedly posted about his struggles with chronic back pain and brain fog.

A former roommate, RJ Martin, told the BBC that while Mangione “never complained”, his back pain at times “prohibited him” from doing “many normal things”, such as surfing or playing volleyball.

Martin – who eventually lost contact with Mangione – said that he believed his former friend “would have never conceived of hurting someone else”.

“There’s no making sense of it,” he added.

A person matching his name and photo had an account on Goodreads, a user-generated book review site, where he read two books about back pain in 2022, one of them called Crooked: Outwitting the Back Pain Industry.

He also gave four stars to a text called Industrial Society and Its Future by Theodore Kaczynski – also known as the Unabomber manifesto. Starting in 1978, Kaczynski carried out a bombing campaign that killed three people and injured dozens of others, until he was arrested in 1996.

In his review, Mangione acknowledged Kaczynski was a violent individual, but also described him as a political revolutionary.