Colorado suspect who was killed after shooting police officer linked to 2019 cold case murder

A suspect who was killed after shooting a police officer this summer is now being linked to a 2019 cold case murder in the state.

A decision letter from the Larimer County district attorney on Friday justified the use of force by four officers in the death of suspect Clayton Pierce, 42. In an update, Fort Collins Police Service also announced investigators found sufficient evidence to prove Pierce was responsible for killing Joseph "Sonny" Brigman, 62, who was found dead at his Fort Collins home in 2019.

According to the Fort Collins PS press release, back in 2019, investigators exhausted all efforts to determine probable cause for criminal charges at the time that Brigman's death was ruled a homicide. 

Then in 2023, Brigman's case was revisited, and that is when Pierce was connected and became a suspect for first-degree murder. 

Ahead of charges being filed with the DA, Fort Collins officers were called to a rollover crash near Grandview Cemetery on July 21 this year. When police arrived, Pierce had a gun on him and shot at first responders, injuring a police officer. Officers shot back and hit Pierce, who died from his injuries. The officer who was hurt was expected to recover at the time of the shooting.

Subsequently, official charges in the murder of Brigman were filed against Pierce with the DA after his death recently on Aug. 20.