California Code, Business and Professions Code - BPC § 6094

(a) Communications to the State Bar relating to lawyer misconduct or disability or competence, or any communication related to an investigation or proceeding and testimony given in the proceeding are privileged, and no lawsuit predicated thereon may be instituted against any person. The State Bar and officers and employees are subject to the rules governing liability of public entities, officers, and employees specified in Division 3.6 (commencing with Section 810) of Title 1 of the Government Code.

Nothing in this subdivision limits or alters the privileges accorded communications to the State Bar or testimony given in investigations or proceedings conducted by it or the immunities accorded complainants, informants, witnesses, the State Bar, its officers, and employees as existed prior to the enactment of this section. This subdivision does not constitute a change in, but is cumulative with the existing law.

(b) Upon application by the State Bar and notice to the appropriate prosecuting authority, the superior court may grant immunity from criminal prosecution to a witness in any State Bar proceeding.