Luigi Mangione, 28, has pleaded guilty to two federal charges of stalking resulting in death for the killing of United Healthcare boss Brian Thompson. He faces up to life in prison when sentenced in December.

Mangione's admission complicates his upcoming state trial, where he faces charges including second-degree murder. His lawyers argue that prosecuting him again for the same crime violates double jeopardy protections, a constitutional safeguard preventing individuals from being tried twice for the same offense. While federal and state governments are considered separate sovereigns, New York has a stronger double jeopardy law that may prevent prosecution for related acts.

Mangione's defense is seeking to dismiss the state charges, arguing the federal plea effectively covers the same criminal conduct. Legal experts suggest the federal plea significantly complicates the state's case, and a ruling on the double jeopardy motion is pending. New York state does not have the death penalty, and that possibility was dismissed earlier in the federal case.