Luigi Mangione's legal team will argue at his state murder trial this fall that he was experiencing an extreme emotional disturbance when he shot and killed UnitedHealthcare CEO Brian Thompson outside a Manhattan hotel on December 4, 2024, a psychiatric defense strategy that a judge revealed Wednesday at a pre-trial hearing at Manhattan Criminal Court that had originally been sealed at the defense's request.
Judge Gregory Carro confirmed the defense strategy after unsealing records related to a hearing held earlier this month that the public was not permitted to attend.
The defense filed notice of its intent to use the extreme emotional disturbance defense in September 2025, but asked the court to keep that filing sealed to prevent it from affecting Mangione's separate and simultaneous federal prosecution, which is governed by different rules and where the same psychiatric defense is not available.
"The reason why we asked for the sealing is that this defense is not available federally and Mr. Mangione is being prosecuted federally and this is prejudicial to his defense to the exact same facts," defense attorney Karen Friedman Agnifilo told the court.
Mangione appeared in court Wednesday wearing a blue suit and a light-colored button-down shirt.
He sat between his attorneys. He is 28 years old. His state murder trial begins September 8.
What The Extreme Emotional Disturbance Defense Actually Means
Extreme emotional disturbance, known in New York law as EED, is what is called an affirmative defense, meaning the defense does not contest the basic facts of what happened but argues that the defendant's mental state at the time of the act reduces his criminal liability.
Under New York law, a defendant who successfully proves EED can have a first-degree murder charge reduced to first-degree manslaughter, which carries a significantly shorter sentence, and potentially be committed to a psychiatric facility rather than prison.
The distinction from a traditional insanity defense is significant.
An insanity defense argues the defendant did not understand what they were doing or did not know it was wrong.
An EED defense argues the defendant understood the act but was so emotionally overwhelmed at the time, by a subjectively reasonable cause, that their conduct should be judged differently than a calculated, fully conscious decision to kill.
New York is one of a relatively small number of states that recognizes EED as a statutory defense.
If Mangione's lawyers can convince a jury that he was in a state of extreme emotional disturbance, caused, presumably, by his documented anger at the American health insurance industry and its practices, when he shot Brian Thompson on a Manhattan sidewalk, he could face consequences substantially different from life in prison.
The Evidence That Makes This Difficult
Legal experts have noted publicly that the EED defense faces a specific challenge in this case that is not present in most cases where such a defense is attempted, what Mangione allegedly did before and after the killing does not look like someone who was emotionally overwhelmed in an uncontrollable way.
A former prosecutor quoted in CNN's analysis of the defense strategy described the fundamental tension. "Normally, someone who acted from EED would be so distraught after the killing that you would want to talk about it. You would not want to flee. You wouldn't try to hide your guilt. What Mangione did after the crime seems to negate the psychiatric defense."
Mangione allegedly shot Thompson, fled the scene, traveled to Altoona, Pennsylvania, approximately 230 miles from Manhattan, and was arrested five days later at a McDonald's, which is the behavior of someone who was trying to evade capture rather than someone rendered irrational by emotional disturbance.
The notebook found in his backpack presents the same evidentiary problem from the other direction.
The notebook, which Judge Carro ruled admissible at the May 18 hearing alongside the 3D-printed pistol used in the killing, contains handwritten entries describing a desire to "wack" a health insurance executive and expressing opposition to what Mangione called "the deadly, greed fueled health insurance cartel."
Methodical, written-out planning is the opposite of the kind of sudden overwhelming emotion that EED describes.
The prosecution will argue that the notebook demonstrates deliberation rather than disturbance.
The Two Trials And The Federal Death Penalty
Wednesday's hearing is part of the state case, the murder prosecution being handled by the Manhattan District Attorney's office. Mangione faces a separate federal prosecution that involves stalking charges and is set to begin October 13, one month after the state trial.
The federal case is the more severe of the two in terms of potential punishment, federal prosecutors are seeking the death penalty, and Mangione could spend his life in prison, or be executed, if convicted of the federal charges.
The reason the EED defense was kept secret from public court records is precisely that federal law does not recognize it as a defense.
Revealing that Mangione's team was preparing to argue extreme emotional disturbance in the state case could have complicated or disadvantaged his federal defense, where the same strategy would not be available.
With the judge's decision to unseal the records Wednesday, that strategic separation no longer holds, both prosecutions now know the state defense.
His federal lawyers have previously argued that the federal trial should occur first, given that it carries the ultimate punishment of death.
Federal courts have different evidentiary rules, different standards for psychiatric defenses and are generally considered a more difficult venue for making the kinds of arguments the state defense team is now confirmed to be pursuing.
Brian Thompson was 50 years old. He was walking toward a Manhattan hotel for UnitedHealth Group's annual investor conference on the morning of December 4, 2024, when he was shot and killed.
The case has attracted extraordinary public attention, and a complicated public response that reflects broader frustration with the American health insurance industry, in the eighteen months since. The trial begins in September.