California Code, Penal Code - PEN § 4758

(a) A county shall be entitled to reimbursement for reasonable and necessary costs incurred by the county with respect to an inmate housed and treated at a state hospital in that county pursuant to Section 2684, including, but not limited to, any trial costs related to a crime committed at the hospital by an inmate housed at the hospital.

(b) Where an inmate referred for treatment to a state hospital pursuant to Section 2684 commits a crime during transportation from prison to the hospital, or commits a crime during transportation from the hospital to the prison, a county that prosecutes the defendant shall be entitled to reimbursement for the costs of prosecution.

(c) No city, county, or other jurisdiction may file, and the state may not reimburse, a claim pursuant to this section that is presented to the Department of Corrections and Rehabilitation or to any other agency or department of the state more than six months after the close of the month in which the costs were incurred.