Luigi Mangione's attorney blasts police, mayor for using the accused CEO killer as 'political fodder'

Luigi Mangione on Monday pleaded not guilty to state murder and terror charges in the fatal shooting of UnitedHealthcare CEO Brian Thompson as his attorney protested his treatment, saying in court that her client is being used as "political fodder" by police and the mayor of New York City.

The 26-year-old Mangione entered the Manhattan courtroom in shackles and under heavy guard. He was dressed in civilian clothes, wearing a maroon sweater over a light-colored shirt, and a pair of chinos.

Mangione spoke into a microphone, saying "Not guilty" to the 11 charges in the indictment, including first-degree murder in furtherance of terrorism. Judge Gregory Carro presided over the arraignment.

The high-profile defendant appeared to not have family in the courtroom. But about two dozen women, who waited in line in the frigid cold for public seats in the courtroom gallery, said they were there to support Mangione. Most of the women wore face masks and a few appeared visibly emotional as Mangione entered the courtroom.

"This is a grave injustice, and that's why people are here," one of the women, who said she arrived at the courthouse at 5 a.m., told ABC News.

During the arraignment, prosecutor Joel Sideman said the Manhattan district attorney’s office has "primary jurisdiction" over the case and will try it before the federal prosecution against Mangione. The accused killer will likely be returned to federal custody, Sideman said.

During the brief court hearing, Mangione sat stone-faced next to his attorney Karen Friedman Angifilo, who was wearing a sweater and a white collared shirt that almost identically matched what her client was wearing.

Agnifilo immediately raised concerns in court that Mangione's rights were being violated, alleging the case was being politicized.

"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," Agnifilo said, calling out New York City Mayor Eric Adams specifically.

Putting her right hand on Mangione's shoulder, Agnifilo prompted a smile from the defendant, saying, "He is a young man, and he is being treated like a human ping pong ball."

Angifilo also slammed last week's extradition of Mangione back to Manhattan to face charges, calling the massive display of force used in the transfer "the biggest staged perp walk I have seen in my career."

She accused the police and Adams of using Mangione as "political fodder."

"What was the New York City mayor doing at this press conference -- that is utterly political," she said, before referencing the mayor's own criminal case. "The New York City mayor should know more than anyone the presumption of innocence."

Following the arraignment, Mangione sat at the defense table conferring with his attorney and a prison consultant hired to be part of his legal team. He signed several forms before officers put him back in handcuffs and led him out of the courtroom.

"We are going to fight these charges, whether it's state or federal," Agnifilo said.

Judge Carro set Mangione's next court date for Feb. 21.

Outside the lower Manhattan courthouse, dozens of people claiming to be Mangione supporters, chanted, "Free, free Luigi" and "the people united will never go for profit." Mangione supporters also held signs, reading, "Health over wealth," "In Luigi we trust." One protester held a sign reading, "United States healthcare stole my livelihood, prosecute malicious profiteers."

A Manhattan grand jury upgraded charges against Mangione last week to include first-degree murder in furtherance of terrorism.

He is also charged in New York with two counts of second-degree murder, one of which is charged as killing as an act of terrorism; two counts of criminal possession of a weapon in the second degree; four counts of criminal possession of a weapon in the third degree; one count of criminal possession of a weapon in the fourth degree; and one count of criminal possession of a forged instrument in the second degree.

He faces a maximum sentence of life in prison without parole if convicted of the state charges.

There is a federal case against Mangione as well. One of the charges, murder through use of a firearm, would make Mangione eligible for the death penalty if he's convicted.

Both cases are in addition to the charges brought against Mangione in Pennsylvania, where he was arrested and where he faces charges including forgery and possession of an unlicensed firearm.

Mangione was transported to New York on Dec. 19 after waiving his right to an extradition hearing that morning in court in Blair County, Pennsylvania.

Agnifilo said the theories of the two cases appear to be in conflict, noting the state case accused Mangione of terrorizing a group of people while the federal case accused him of stalking an individual.

Danielle Filson, a spokesperson for Manhattan District Attorney Alvin Bragg, said this week that "the state case will proceed in parallel with any federal case."

Mangione’s next scheduled court date for his federal case is Jan. 18.