Cal. Government Code § 19993.2

The department shall prescribe rules and regulations which: (a) Define the use of state-owned motor vehicles which constitutes use in the conduct of state business and distinguish such use from misappropriation for private use; (b) Prescribe the procedure for determining and collecting from the employee responsible for the misuse the actual costs to the state attributable to misuse of state-owned motor vehicles and the disposition of such collections; (c) Prescribe the records and reports to be kept and made by state agencies relating to the use of state-owned motor vehicles to the end that misuse may be discovered with a minimum of recordkeeping; (d) Govern the storage of state-owned motor vehicles in those locations where storage space, under the jurisdiction of the Department of General Services, is available for storage of state-owned motor vehicles; (e) Prescribe the procedures to be used in the operation of state-owned vehicles as commute vehicles in a state carpool or vanpool program.