A judge said Wednesday that Luigi Mangione's lawyers will assert a psychiatric defense in his state murder trial in New York.
His lawyers told Judge Gregory Carro they will try to show he was suffering from "extreme emotional disturbance at the time of the occurrence."
The state trial is set to begin on Sept. 8, and the judge announced he would unseal court records related to the defense's plan.
Mangione has pleaded not guilty in both the federal and state cases, and he faces federal stalking charges that can bring a maximum sentence of life in prison; federal murder and firearms charges were dropped earlier this year.
UnitedHealth Chief Executive Brian Thompson, 50 and a father of two, was shot from behind by a masked gunman on Dec. 4, 2024, as he walked into a Manhattan hotel for an annual investor conference.