The Contra Costa County Office of the Sheriff and the Contra Costa District Attorney’s Office are currently jointly investigating an in-custody death that occurred at the Martinez Detention Facility.
On Thursday, January 8, 2026, at about 5:38 AM, Contra Costa Health medical staff at MDF responded to a housing module for a report of head injuries that an inmate apparently sustained as a result of him purposely banging his head while housed in a cell. Minutes later, the fire department and an ambulance were called to transport the inmate to a local hospital.
At about 8:30 AM, the inmate was medically cleared at the hospital. He was uncooperative with deputy sheriffs while being transported back to MDF. While at MDF he was given medication by medical staff. At about 5:48 PM, a deputy sheriff found the inmate unconscious inside his cell. Jail medical staff responded while deputies performed CPR. The fire department and an ambulance also responded and later declared the inmate deceased. The county- wide law enforcement involved fatal incident protocol was invoked.
The inmate is identified as 61-year-old Kirk Richardson of Concord. On December 31, 2025, Richardson was arrested by the Concord Police Department for murder. He was booked into MDF on two counts of murder and had been held since that time.
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- Jan 3, 2026 – Murder Charges Filed Against Concord Man Accused of Killing Parents: The Concord Police Department announced that murder charges have been filed against a man accused of killing his parents. The incident occurred around 7:00 am on December 31, 2025 when officers responding to a 9-1-1 call reporting a family disturbance in the 3900 block of Walnut Avenue. When officers arrived, they located two individuals deceased from gunshot wounds. A third occupant at the residence was detained and subsequently arrested in connection with the incident. On Friday, Concord Police said the case was referred to the Contra Costa County District Attorney’s Office for filing considerations where the District Attorney’s Office filed two counts of Murder (PC187) with enhancements for use of a firearm, against 61 year Kirk Richardson for the murder of his parents. Richardson remains in custody and is being held in lieu of $4 million bail.
- Dec 31, 2025 – Concord Police Investigating Homicide on Walnut Ave