Luigi Mangione appeared in a New York City courtroom for the first time since his arraignment, facing charges in the fatal shooting of UnitedHealthcare CEO Brian Thompson.

Mangione, 26, arrived in court on Friday, February 21, with his hands and ankles shackled for his first hearing after he was arraigned on state murder and terror charges in late December. He had previously pleaded not guilty to 11 counts, including first-degree murder, second-degree murder as an act of terrorism and multiple weapons offenses, in Manhattan Supreme Court.

During the hearing, Mangione’s lawyer, Karen Friedman Agnifilo, said there were “very serious issues” with some of the evidence in the case.

“We are concerned that Luigi’s constitutional rights were violated in Pennsylvania,” Agnifilo told reporters in a press conference outside the courthouse following the hearing, per ABC News. Agnifilo claimed there were “serious search and seizure issues” they would be litigating in his state cases in Pennsylvania and New York as well as his federal case.

In addition, the attorney referenced the HBO documentary that was released on February 17, 2025, and said New York mayor and police officers have discussed evidence the defense has not yet received. Agnifilo also said an actor portraying Mangione had read from a journal that was allegedly his, but the defense had not received that from the prosecution.

Thompson, 50, was gunned down at approximately 6:45 a.m. on December 4, 2024, while he was walking to the Hilton Hotel in Midtown Manhattan for a shareholder’s conference. The CEO was later pronounced dead at a local hospital. He is survived by his wife, Paulette “Pauley” Thompson, and their two children.

Thompson’s shooter, a masked assailant wearing a hood, fled the scene on foot before taking an e-bike into Central Park. He left behind a backpack containing a jacket with Monopoly money, but no weapon.

One day later, New York authorities released surveillance photos that showed a portion of the shooter’s face from HI New York City Hostel on Amsterdam Avenue near 104th Street in Manhattan. It was revealed that the suspect had arrived in Manhattan on November 24, 2025, and checked into the hostel. He checked out on November 29, 2024, before checking in again the following day with a fake New Jersey ID.

Mangione was arrested at a McDonald’s in Altoona, Pennsylvania, on December 9, 2024. He allegedly was in possession of a gun and silencer that were similar to the ones used in the shooting, as well as the fake New Jersey ID that was reportedly used to check into the hostel. He also allegedly had a “manifesto” on his person when police placed him under arrest. In the manifesto allegedly written by Mangione, he criticized the healthcare industry and claimed it was corrupted and driven by profit.

Since his arrest, Mangione has garnered a cult-like following, with women appearing in the courtroom to show their support. However, Agnifilo has expressed concern that his growing notoriety could impact his right to a fair trial.

“I am very concerned about my client’s right to a fair trial in this case. He is being prejudiced by some statements made by public officials,” Friedman Agnifilo said in a statement, per ABC News. “He is a young man, and he is being treated like a human ping pong ball.”