Homicide at California Medical Facility prison in Vacaville
Joe Duty. Jr. is being investigated for a homicide inside CMF. Photo: CDCR
VACAVILLE, Calif. - California Department of Corrections and Rehabilitation officials are investigating the death of an incarcerated man at the California Medical Facility in Vacaville as a homicide.
What we know:
Stephenson C. Kim died on Monday, according to a news release from CDCR, the state's prison agency.
Kim's death stemmed from a fight with another incarcerated man, Joe Duty Jr., on Jan. 4 at 7:20 p.m. in a housing unit.
Kim was found unconscious after the fight and was taken to the hospital, according to CDCR.
Duty was placed in restricted housing and will remain there, pending an investigation by the CMF Investigative Services Unit and the Solano County District Attorney’s Office. The Office of the Inspector General has been notified.
What we don't know:
What the fight was about has not been revealed.
Stephenson Kim died on Jan. 12, 2026 at CMF in Vacaville. Photo: CDCR
Kim, 45, came from Orange County on May 23, 2012. He was sentenced to life without the possibility of parole for first degree murder and attempted first degree murder with enhancements for the intentional discharge of a firearm causing great bodily injury or death.
Duty, 30, came from San Joaquin County on Feb. 14, 2025. He was sentenced to 14 years for rape with force of a minor 14 years of age or older and lewd or lascivious acts against a child under 14 with force.
Local perspective:
California Medical Facility was established in 1955 by the California Legislature to provide a centrally located facility to meet the medical, psychiatric, and dental health care needs of men incarcerated in California. CMF is a medium-security medical facility in Vacaville.