Mangione Charged in UnitedHealthcare CEO Murder

Mangione was apprehended with a 3D-printed gun matching three shell casings marked "deny," "defend," and "depose" found at the crime scene. He also possessed a silencer, a 262-word manifesto, a "to-do list," and several false ID cards.

Thompson was shot in the back on December 4 outside the New York Hilton Midtown. Mangione is currently held without bond in Pennsylvania, fighting extradition to New York, where he faces 15 years to life for second-degree murder.

First-degree murder, carrying stiffer penalties, applies to specific aggravating circumstances like targeting judges or police, or acts of terrorism. Prosecutors are exploring if the plot was terrorism-inspired, which could upgrade the charge, as noted by David Shapiro of John Jay College of Criminal Justice.

Federal charges are also possible if Mangione crossed state lines to commit violence, according to former federal and state prosecutor Elie Honig, given he reportedly traveled from Atlanta to New York. Mangione pleaded not guilty to all charges, his attorney Thomas Dickey stated.

The high-profile killing has raised concerns among insurance company executives about potential copycats.