It was a stunning day in federal court as 28-year-old Luigi Mangione pleaded guilty to federal charges of stalking resulting in death of UnitedHealthcare CEO Brian Thompson. Mangione was emotionless as he described how and why he murdered Thompson, detailing years of back pain and frustration with the insurance industry. It’s unclear now what will happen to the New York State murder charge against Magnione, his trial set to start on Sept 8th.