Luigi Mangione murder trial: Judge to allow gun, alleged diary confession as evidence

A Manhattan state judge presiding over the murder trial against Luigi Mangione will allow a gun and alleged diary confession of the killing of UnitedHealthcare CEO Brian Thompson to be admitted at trial, ruling that the police search of the defendant's backpack after his arrest in a Pennsylvania McDonald's did not violate the suspect’s rights.

Monday's ruling marked a significant blow to the defense case and will allow a jury to hear what Mangione wrote in the days before the early morning shooting of the health insurance executive on Dec. 4, 2024, and what he was thinking in the days after.

A Manhattan grand jury indicted him in December 2024 on murder and six weapons possession charges, as well as one count for possession of a fake ID.

Prosecutors charge that Mangione, an Ivy League graduate who comes from an affluent Maryland family, gunned down Thompson outside an investor’s conference in midtown Manhattan as a protest against the country’s dysfunctional healthcare system.

After Thompson’s killing, city, state and federal law enforcement went on a five-day hunt for the gunman. Police released several photos of the suspect, hiding most of his face with a medical mask. The most prominent feature was his thick, dark eyebrows.

It wasn’t until Dec. 9, 2024, that a tip from an Altoona McDonald’s worker to local police led to Mangione’s arrest in Pennsylvania.

Altoona police Sgt. Joseph Detwiler said he did not believe he would find the suspect in the country's biggest manhunt of the time. He even bet his supervisor a sandwich that it would not be a credible tip.

Instead, almost immediately, the officer testified during a previous hearing, he recognized Mangione’s eyebrows from the NYPD bulletins looking for leads in the shooting.

Initially, Mangione gave police a fake New Jersey driver’s license, but as more officers arrived at the fast food restaurant, he eventually gave his real identity.

During his arrest, police searched his bag, finding a gun, ammunition and a red notebook in which Mangione had written notes about travel from New York to Pittsburgh, and mused about changing his look and plucking his eyebrows, authorities said.

The notebook also allegedly contained a letter “to the Feds:” about his plan to “wack [sic] the CEO at the annual parasitic bean-counter convention.”

The judge's decision allows both sides to claim they were correct on the legality of the search.

Defense lawyer Karen Friedman Agnifilo argued in her motion to suppress the search discovery that the Pennsylvania police violated her client’s right to be protected against unlawful searches. They noted that police didn’t get a search warrant until hours later.

At hearings on the search discovery last year, police body-worn camera footage showed officers moving the bag out of Mangione’s reach before opening it.

It was then, at the McDonald’s, that officers found ammunition clips and then decided to take the bag back to police headquarters. That search, state Supreme Court Justice Gregory Carro ruled, violated Mangione's rights. The judge determined that there was no emergency, like a ticking time bomb, that would require a search without a warrant.

Defense attorneys noted that the bag was placed in one vehicle when it left the restaurant and arrived in the precinct in a different vehicle.

Once they were in the station house, officers went through the bag again, this time pulling out all the contents and photographing them to create a record, in keeping with the arrest intake procedure. Inside the precinct, the footage shows officers pulling a 3D-printed automatic handgun from the backpack.

Carro determined that Altoona police did not violate Mangione's rights when they took inventory of the contents of the bag when they found the notebook, ammunition, a silencer and the handgun. That evidence will be allowed at trial because it was lawfully obtained in the subsequent search, the judge ruled.

The decision, which parallels a similar decision in the federal murder case against Mangione, overcomes a significant hurdle for the Manhattan District Attorney's Office to put on its case.

Manhattan federal prosecutors have also charged Mangione with crossing state lines to stalk and kill Thompson, saying he had planned for months before the fatal shooting. He's also been charged with federal weapons charges.

The state trial is scheduled to start on Sept. 8, followed by the federal trial in the beginning of 2027.