Cal. Civ. Proc. Code § 1297.271

The arbitral tribunal, or a party with the approval of the arbitral tribunal, may request from the superior court assistance in taking evidence and the court may execute the request within its competence and according to its rules on taking evidence. In addition, a subpoena may issue as provided in Section 1282.6, in which case the witness compensation provisions of Section 1283.2 shall apply.