Lawyers for Luigi Mangione, the 28-year-old accused of fatally shooting UnitedHealthcare chief executive Brian Thompson in New York in December 2024, will mount a psychiatric defence at his state murder trial, arguing that he was suffering from "extreme emotional disturbance" at the time of the killing. New York Judge Gregory Carro confirmed the defence's strategy in court on Wednesday, revealing that Mangione's legal team had first raised the possibility in a letter filed under seal last year and formally confirmed their decision at a closed hearing on 3 June.
If a jury accepts the defence, it would be legally obliged to convict Mangione of manslaughter rather than murder. Manslaughter carries a maximum sentence of 25 years in prison, whereas a murder conviction could result in life imprisonment. The extreme emotional disturbance argument does not amount to a plea of not guilty by reason of insanity — it would not absolve Mangione of responsibility for Thompson's death, nor would it lead to a psychiatric facility rather than prison. To succeed, his lawyers must demonstrate that the disturbance was so severe it stripped him of self-control, that he held what he believed to be a reasonable explanation for it, and that he killed Thompson while under its influence. Judge Carro said he does not expect the development to delay the trial, which is scheduled to begin with jury selection on 8 September.
The case has drawn wide public attention since Thompson, a 50-year-old father of two, was shot from behind by a masked gunman on 4 December 2024 as he walked to a Manhattan hotel for UnitedHealth Group's annual investor conference. Police noted that the words "delay," "deny" and "depose" — a phrase associated with criticism of insurance companies' claims practices — were written on the ammunition. A 3D-printed pistol recovered from Mangione's belongings has been matched to the weapon used in the shooting, and a notebook describing an intent to target a health insurance executive was also admitted as evidence at a May hearing.
Mangione, an Ivy League graduate from a wealthy Maryland family, was arrested five days after the shooting at a McDonald's restaurant in Pennsylvania. He faces parallel state and federal proceedings; the federal case, which involves stalking charges and also carries a potential life sentence, is scheduled for trial on 13 October. Crucially, the extreme emotional disturbance defence is not available under federal law, and Mangione's lead attorney, Karen Friedman Agnifilo, argued that unsealing the psychiatric defence materials could prejudice his federal case, since both prosecutions concern the same underlying facts. Judge Carro said he would unseal the transcript of the secret June hearing and related records once redactions are made, and that Mangione may be transferred to New York City's Rikers Island jail complex to facilitate a psychiatric evaluation by a prosecution-appointed psychiatrist. His next pretrial hearing is set for 11 August.