California Code, Public Utilities Code - PUC § 1770

(a) Within 30 days after the commission issues its order or decision denying the application for a rehearing or, if the application is granted, within 30 days after the commission issues its decision on rehearing, an aggrieved party may petition for a writ of review in the California Supreme Court for the purpose of determining the lawfulness of the original order or decision or of the order or decision on the rehearing.  If the writ is issued, it shall be made returnable at a time and place specified by court order and shall direct the commission to certify its record in the case to the court within the time specified.  No order of the commission interpreting, implementing, or applying the provisions of Article 5.7 (commencing with Section 849) of Chapter 4 of Part 1 of Division 1 shall be subject to review in a court of appeals.

(b) The petition for review shall be served upon the executive director of the commission either personally or by service at the office of the commission.

(c) For purposes of this section, the issuance of a decision or the granting of an application shall be construed to have occurred on the date when the commission mails the decision or grant to the parties of the action or proceeding.

(d) To the extent that the provisions do not conflict, provisions in this article shall apply to actions under this section.