Cal. Corporations Code § 31401

(a) The commissioner may in his discretion (1) make such public or private investigations within or outside of this state as he deems necessary to determine whether any person has violated or is about to violate any provision of this law or any rule or order hereunder or to aid in the enforcement of this law or in the prescribing of rules and forms hereunder, and (2) publish information concerning the violation of this law or any rule or order hereunder. (b) For the purpose of any investigation or proceeding under this law, the commissioner or any officer designated by him may administer oaths and affirmations, subpoena witnesses, compel their attendance, take evidence, and require the production of any books, papers, correspondence, memoranda, agreements, or other documents or records which the commissioner deems relevant or material to the inquiry. (c) In case of contumacy by, or refusal to obey a subpoena issued to, any person, the superior court, upon application by the commissioner, may issue to the person an order requiring him to appear before the commissioner, or the officer designated by him, there to produce documentary evidence, if so ordered, or to give evidence touching the matter under investigation or in question. Failure to obey the order of the court may be punished by the court as a contempt. (d) No person is excused from attending and testifying or from producing any document or record before the commissioner, or in obedience to the subpoena of the commissioner or any officer designated by him, or in any proceeding instituted by the commissioner, on the ground that the testimony or evidence (documentary or otherwise) required of him may tend to incriminate him or subject him to a penalty or forfeiture; but no individual may be prosecuted or subjected to any penalty or forfeiture for or on account of any transaction, matter, or thing concerning which he is compelled, after validly claiming his privilege against self-incrimination, to testify or produce evidence (documentary or otherwise), except that the individual testifying is not exempt from prosecution and punishment for perjury or contempt committed in testifying.