California Code, Government Code - GOV § 823

Neither the widow, widower, nor the heirs of a peace officer, as defined in Sections 830.1, 830.2, and 830.32 of the Penal Code, shall be liable individually for any injury or death that may result from an act or omission of a peace officer that occurs in his or her line of duty, including an act or omission not directly related to the officer's death, if the officer was slain while in the line of duty.  Nothing in this section shall preclude any action from being brought against the estate of the peace officer.