Luigi Mangione attorneys to present psychiatric defense in fatal shooting of United Healthcare CEO Brian Thompson

The lawyers for Luigi Mangione, the Maryland man accused of fatally shooting a UnitedHealthcare executive outside a Manhattan hotel in 2024, will present a psychiatric defense at his upcoming state trial in September, they said in court on Wednesday.

Defense attorneys submitted notice of "extreme emotional disturbance at the time of the occurrence" during a sealed proceeding on June 3, Manhattan Supreme Court Justice Gregory Carro said during the morning hearing.

The announcement marks a major pivot in the case for the defense team. Mangione's lawyers will now tack from denying their client committed the crime to putting on a case proving that his mental state caused a "profound loss of self-control" that led to the killing.

Mangione, an Ivy League graduate and scion of a wealthy family, has pleaded not guilty to second-degree murder, criminal possession of a weapon, illegal possession of ammunition and carrying a fake New Jersey driver’s license.

Authorities said he shot health insurance CEO Brian Thompson in the back early on Dec. 4, 2024, outside the Hilton on Sixth Avenue in midtown.

The judge dismissed previous terrorism charges and, on Wednesday, he dropped the ammunition charges because they were the result of an illegal search of Mangione's bag during his arrest in Altoona, Pennsylvania.

Manhattan federal prosecutors have also charged Mangione on federal stalking and murder charges.

Defense lawyer Karen Friedman Agnifilo said that the defense team had to be circumspect about their strategy because the psychiatric defense is not an option in the federal case against Mangione.

“This is prejudicial to his federal case,” said Friedman Agnifilo, who is also representing Mangione in the federal case..

Prosecutors with the Manhattan District Attorney’s Office had asked the judge in September to prohibit the defense attorneys from using a psychiatric defense in the case, citing a law that mandates notification for such a strategy within 30 days of a not guilty plea.

Friedman Agnifilo argued that her team needed to see all the evidence that prosecutors and police had gathered against her client before making a decision on that defense.

On May 18, after a lengthy evidentiary hearings regarding the search of Mangione's bag during his arrest, Carro ruled that a 3-D printed handgun, silencer and a red journal containing writing that authorities have called a "manifesto" could be admitted at trial.

During the hearings, prosecutors showed video surveillance of a masked man approaching Thompson, a married father of two, from behind, firing three shots and then fleeing.

The killing stunned and fascinated the public, not just for the brutality of the crime, but because of the target. The words "depose," "delay" and "den[y]" were written on shell casings found at the scene in an apparent reference to a book detailing the ways health insurance companies reject coverage.

Thompson’s death appeared to bring to the surface the frustrations that many Americans feel about healthcare. Supporters began showing up at his court appearances and there were reported copy cat shootings across the country in the wake of Thompson's death.

Mangione's notebook appeared to explain why he targeted the UnitedHealthcare CEO.

"I do apologize for any strife or trauma, but it had to be done," he allegedly wrote. "Frankly, these parasites simply had it coming. A reminder: the US has the #1 most expensive healthcare system in the world, yet we rank roughly #42 in life expectancy, UHC is the 5th largest company in the US by market cap, behind only Apple, Google, Walmart. It has grown and grown, but has our life expectancy? No. "

Prosecutors have portrayed Mangione as a cold, calculated killer -- someone who plotted out the crime over months, traveling from out of town, scoping out the area where the shooting took place ahead of time and planning his escape.

The extreme emotional disturbance defense shifts the burden of proof to Mangione's team to show that his frame of mind caused him to lose control. They also have to convince the jury that there was a reason for him to become overwhelmed by his emotions.

If the panel agrees that his emotional state was a factor in the crime, they must acquit him of second-degree murder and find him guilty of a reduced charge of manslaughter. If successful, that verdict would make him eligible for a reduced prison time.

Seidmann told the court that he anticipated the defense team would use the mental health strategy to further delay the trial, something he said that prosecutors would “vigorously oppose.”

“The family is entitled to their day in court,” he said. “The family of Brian Thompson has the absolute right to know the why and who.”

The Manhattan prosecutor also said that defense attorneys had been “stonewalling” the district attorney’s office regarding the details of Mangione’s psychiatric defense.

“We don’t know the expert. We don’t know the theory of the [extreme emotional disturbance,]” Seidmann said. “In order for them to go forward, they need to know what maladies this defendant suffers and how it contributed to [the crime.]”

The defense lawyer objected to Seidmann’s complaints, calling it “completely unnecessary carrying on,” adding that they have not asked for any delay.

Carro ordered the defense team to turn over the information from the psychological evaluation to prosecutors by Thursday.

The case will be back in court on August 11 to discuss questions in the jury questionnaire and other trial-related issues.