Luigi Mangione's legal team opted Thursday to not use the argument that their client was experiencing extreme emotional disturbance at the time of the murder of UnitedHealthcare CEO Brian Thompson in 2024.

Mangione has been accused of fatally shooting Thompson in New York City two years ago, but has pleaded not guilty to murder and weapons charges. 

Judge Gregory Carro said Wednesday he would unseal records related to cases in which defendants admit to the charges but argue they can't be held liable because they were experiencing an extreme emotional disturbance at the time, and the judge gave Mangione's team until Thursday to produce evidence to support the argument.

If the defense had opted to use the extreme emotional disturbance justification for the murder charge and succeeded, the crime would have dropped from second-degree murder to first-degree manslaughter, according to NBC News.

Prosecutors have claimed they found evidence in the defendant's diary, which investigators seized during his arrest, that allegedly show he planned to kill Thompson. Mangione's legal team argued the diary was seized illegally but Carro has ruled it admissable. 

“Wack the CEO at the annual parasitic bean-counter convention,” the diary says, according to a court filing from the district attorney’s office. “It’s targeted, precise, and doesn’t risk innocents.”

Mangione’s trial is scheduled to begin in September.

Misty Severi is a news reporter for Just The News. You can follow her on X for more coverage.