Brian Thompson

Mangione's preparations

The suspect arrived in New York City on November 24, 2024, on a Greyhound bus. The bus route began in Atlanta, Georgia, but authorities do not know from which city or town he boarded. The day of his arrival, he checked into the HI New York City Hostel on the Upper West Side of Manhattan with a falsified New Jersey identification card; he paid for his stay in cash. He stayed at the hostel for all but one night of the 10 days he was in New York City, checking out on December 3.

After his guilty plea, Mangione revealed that he had contacted UnitedHealthcare to gain access to details of the event Thompson was heading to by posing as an investor from a multibillion dollar firm.

Thompson and UnitedHealthcare

Brian Robert Thompson (July 10, 1974 – December 4, 2024) was the chief executive officer (CEO) of UnitedHealthcare, the insurance arm of UnitedHealth Group, from April 2021 until his death. He had worked for UnitedHealthcare since 2004. UnitedHealthcare insures 49 million Americans and generated $281 billion in revenue for the 2023 fiscal year. At the time of Thompson's death, the company was the largest health insurer in the United States.

UnitedHealthcare had repeatedly faced criticism for its approach to handling claims. It and other insurers were named in an October 2024 report from the United States Senate Homeland Security Permanent Subcommittee on Investigations showing a surge in prior authorization denials for Medicare Advantage patients. Reports of increasing rates of prior authorization denials prompted investigations by ProPublica and the United States Senate, investigations which were described as a "stain" on Thompson's time of leadership by Fortune. According to Thompson's widow, he had been receiving threats related to a "lack of [insurance] coverage". In May 2024, a lawsuit was filed against Thompson along with Stephen Hemsley and two other senior executives for alleged fraud and insider trading due to failing to disclose an antitrust investigation into the company by the United States Department of Justice and by selling stock options before the probe was made public.

Health insurance corporations

After Thompson's death, UnitedHealthcare's parent company, UnitedHealth Group, published a statement on Facebook detailing the death and their official condolences. Though the post's comment section was deactivated, over 100,000 Facebook users responded to the post with a "Haha" (or "laughing") reaction. UnitedHealth Group CEO Andrew Witty defended the company's claim denial practices in an internal video which was leaked after the fatal shooting of Thompson. Recorded on December 5, the day after Thompson's death, Witty emphasized the company's role in ensuring "safe and appropriate" care and that the insurance giant will continue to prevent "unnecessary care”. Two months after the shooting, UnitedHealth hired a defamation law firm to take action against social media posts critical of the company. Prosecutors alleged that the killing had scared 40 UHC executives into hiring bodyguards.

The killing significantly contributed to "months of tumult" at UnitedHealthcare. The public response led to growing negative perceptions of the company, which former chief medical officer Archelle Georgiou said "gets in the way of innovation and collaboration". Since the killing, the company's stock fell from $610 a share to $308. The company faced multiple lawsuits and investigations, had a decrease in profits, and in May, Witty abruptly resigned.

UnitedHealthcare, Blue Cross Blue Shield, and CVS Health, which operates Aetna, all removed photographs and other information about their executive leadership from their websites following Thompson's killing. Managed care provider Centene cancelled their in-person investor's day which had been scheduled for December 12, and instead planned a virtual conference. The days following Thompson's death saw a surge in inquiries about protective services and security for CEOs and corporate executives, according to private security firm Allied Universal. One former health insurance executive was quoted by the Financial Times as saying that threats against health insurance companies are common, and that "We'd have times when you'd deny proton laser therapy for a kid with seizures and the parent would freak out." Michael Sherman, the former chief medical officer at Point32Health, justified the concerns of health insurance executives, saying, "It doesn't seem paranoid to worry that someone who's had services denied that they may believe are important might be in an emotionally unstable state."

Politicians

Several public officials, including Minnesota governor Tim Walz and Senator Amy Klobuchar, expressed dismay and offered condolences to the family; Walz said that he knew Thompson. Maryland state delegate Nino Mangione, cousin of Luigi Mangione, said: "Our family is shocked and devastated by Luigi's arrest. We offer our prayers to the family of Brian Thompson, and we ask people to pray for all involved".

Outgoing White House Press Secretary Karine Jean-Pierre said that the government said that "violence to combat any sort of corporate greed is unacceptable". Pennsylvania Governor Josh Shapiro commented that "Some attention in this case, especially online, has been deeply disturbing, as some have looked to celebrate instead of condemning this killer." At the time President-elect Donald Trump also condemned the killing and called celebration of Mangione "a sickness". Outgoing Department of Homeland Security secretary Alejandro Mayorkas said that social media rhetoric about the killing was alarming, and that "It speaks of what is really bubbling here in this country, and unfortunately we see that manifested in violence, the domestic violent extremism that exists".

California Democratic House representative Ro Khanna said, "There is no justification for violence" and added that the public reaction to Thompson's killing did not surprise him because "We waste hundreds of billions a year on health care administrative expenses that make insurance CEOs and wealthy stockholders incredibly rich while 85 million Americans go uninsured or underinsured". Massachusetts Democratic Senator Elizabeth Warren stated, "The visceral response from people across this country who feel cheated, ripped off, and threatened by the vile practices of their insurance companies should be a warning to everyone in the health care system. Violence is never the answer, but people can be pushed only so far." New York Democratic Representative Alexandria Ocasio-Cortez said, "This is not to say that an act of violence is justified, but I think for anyone who is confused or shocked or appalled, they need to understand that people interpret and feel and experience denied claims as an act of violence against them." Vermont senator Bernie Sanders condemned the killing, but said the public response showed that many people were angry at health insurance companies and their practices. Oregon senator Ron Wyden commented that "I've long said violence, murder, are always unacceptable, always. But I think that there is a context, you know, here that is hugely important".

Three fired cartridge cases alongside three unfired cartridges were found at the scene. The words "delay", "deny", and "depose" were written on the cases. "Depose" was inscribed on a casing from a round fired into Thompson, while "delay" was marked on an unfired cartridge ejected as the shooter appeared to be clearing a jam. The three words are similar to the phrase "Delay, Deny, Defend", a phrase adopted by critics of the American healthcare industry alluding to health insurance companies' efforts to not pay out claims. Accordingly, police stated they were investigating whether the words suggest the killer's motive.

A water bottle, candy wrapper, and phone were recovered from the scene and are believed to be connected to the shooter. Police said they believed they found the shooter's backpack in Central Park on December 6, 2024. The backpack contained a Tommy Hilfiger jacket and Monopoly money.

The New York City Police Department offered a reward up to $10,000 for information about the shooter on December 4, 2024. The following day, authorities released images of a suspect taken by surveillance cameras at the hostel and a Starbucks café. Two stills show the suspect's face, including one with him smiling widely at a female desk attendant at the hostel. Sources told CBS the front desk worker asked to "see his pretty smile." The FBI joined the investigation and separately offered a reward of up to $50,000 for information leading to an arrest and conviction.

The shooter was described by police as a white man, approximately 6 ft 1 in (185 cm) tall, wearing a light brown or cream-colored hooded jacket, dark pants, and black sneakers with white soles. He had a gray backpack and concealed his face with a black face mask. Police said the suspect appeared to be proficient in the use of firearms and was described as being "extremely camera savvy".