The December 22, 2025 crash on State Route 4 in Antioch killed 27-year-old Phoenix Corwen Dunn, who was struck by an on-duty Contra Costa County District Attorney Senior Inspector.
According to the Contra Costa County District Attorney's Office, Dunn was struck and killed by a county car driven by the inspector while he was on duty.
CHP Investigation
The California Highway Patrol investigation was ongoing.
Those findings echo the details that first emerged in the days after the crash. The Antioch Herald reported at the time that the 27-year-old suspect, who may have spotted police lights, jumped a fence and ran onto the freeway, where he was struck by the on-duty Contra Costa County District Attorney Senior Inspector. The outlet also reported that the inspector and Antioch police officers rendered medical aid immediately, but the man died at the scene.
No Foot Pursuit, Police Say
The Antioch Herald reported that responding Antioch Police Department officers were not involved in any foot pursuit of the suspect at the time he ran onto the highway. Patch reported the crash happened at about 10:35 a.m. near Delta Fair Boulevard in Antioch.
Why an Outside Agency Reviewed the Case
Contra Costa County outlines the purpose of this kind of outside review in its description of the Law Enforcement Involved Fatal Incidents Protocol, stating that such investigations are conducted to determine whether the individuals involved may be criminally liable, according to Contra Costa County's own published materials.
The crash remains a sobering entry in the record of highway incidents involving law enforcement vehicles in Contra Costa County.
