Cal. Gov. Code § 31725
Permanent incapacity for the performance of duty shall in all cases be determined by the board.
If the medical examination and other available information do not show to the satisfaction of the board that the member is incapacitated physically or mentally for the performance of his duties in the service and the member's application is denied on this ground the board shall give notice of such denial to the employer. The employer may obtain judicial review of such action of the board by filing a petition for a writ of mandate in accordance with the Code of Civil Procedure or by joining or intervening in such action filed by the member within 30 days of the mailing of such notice. If such petition is not filed or the court enters judgment denying the writ, whether on the petition of the employer or the member, and the employer has dismissed the member for disability the employer shall reinstate the member to his employment effective as of the day following the effective date of the dismissal.
Ca. Gov. Code § 31725