Cal. Government Code § 53298

(a) No local agency officer, manager, or supervisor shall take a reprisal action against any employee or applicant for employment who files a complaint pursuant to Section 53297. (b) This article is not intended to prevent a local agency from taking, directing others to take, recommending, or approving any personnel action with respect to any employee or applicant for employment if the local agency reasonably believes that the action or inaction is justified on the basis of separate evidence which shows any of the following: (1) The employee’s complaint has disclosed information that he or she knows to be false or has disclosed information without regard for the truth or falsity thereof. (2) The employee’s complaint has disclosed information from records which are closed to public inspection pursuant to law. (3) The employee’s complaint has disclosed information which is confidential under any other provision of law. (4) The employee was the subject of an ongoing or existing disciplinary action prior to the disclosure of information with the local agency. (5) The employee has violated any other provision of the local personnel rules and regulations, has failed to perform assigned duties, or has committed any other act unrelated to the disclosure that would otherwise be subject to personnel action. (c) It is not a violation of this article for an officer, manager, or supervisor to take disciplinary action against an employee if that officer, manager, or supervisor had no prior knowledge that a complaint had been filed by that employee.