California Code, Public Utilities Code - PUC § 307

(a) The commission may appoint as attorney to the commission an attorney at law of this state, who shall hold office during the pleasure of the commission.

(b) The attorney shall represent and appear for the people of the State of California and the commission in all actions and proceedings involving any question under this part or under any order or act of the commission.  If directed to do so by the president, except as otherwise directed by vote of the commission, the attorney shall intervene, if possible, in any action or proceeding in which any such question is involved.

(c) The attorney shall commence, prosecute, and expedite the final determination of all actions and proceedings directed or authorized by the president, except as otherwise directed or authorized by vote of the commission, advise the commission and each commissioner, when so requested, in regard to all matters in connection with the powers and duties of the commission and the members thereof, and generally perform all duties and services as attorney to the commission that the president, or vote of the commission, may require of him.