Cal. Lab. Code § 1176

The commission or any members thereof may subpena witnesses and administer oaths. All witnesses subpenaed by the commission shall be paid the fees and mileage fixed by law in civil cases. In case of the failure of a person to comply with an order or subpena of the commission or any member thereof, or in the case of the refusal of a witness to testify to any matter regarding which he may lawfully be interrogated before any wage board or the commission, it shall be the duty of the superior court or judge thereof, on the application of a member of the commission, to compel obedience in a manner by which such obedience could be compelled in a proceeding pending before the court.