Suppose a public employee maliciously and without probable cause files a lawsuit or initiates an administrative proceeding against you.   You succeed in obtaining a dismissal, but would like to hold that employee accountable.   Accountability may not be attainable because Government Code Section 821.6 broadly immunizes public employees:

A public employee is not liable for injury caused by his instituting or prosecuting any judicial or administrative proceeding within the scope of his employment, even if he acts maliciously and without probable cause.

This is a high level of immunity given the meaning of "malice".   According to California Civil Jury Instruction No. 3114 a person acts with "malice" when that person:

acted with intent to cause injury or that [his/her/nonbinary pronoun] conduct was despicable and was done with a willful and knowing disregard of the rights or safety of another.  A person acts with knowing disregard when the person is aware of the probable dangerous consequences of the person’s conduct and deliberately fails to avoid those consequences.  “Despicable conduct” is conduct that is so vile, base, or contemptible that it would be looked down on and despised by reasonable people.

Nonetheless, the California Supreme Court yesterday did  somewhat cabin the immunity conferred by Section 821.6, holding that Section 821.6 "does not broadly immunize police officers or other public employees for any and all harmful actions they may take in the course of investigating crime".  Leon v. County of Riverside, S. Ct. Case No. S269672 (June 22, 2023).