Cal. Labor Code § 5703.5

(a) The appeals board, at any time after an application is filed and prior to the expiration of its jurisdiction may, upon the agreement of a party to pay the cost, direct an unrepresented employee to be examined by a qualified medical evaluator selected by the appeals board, within the scope of the qualified medical evaluator’s professional training, upon any clinical question then at issue before the appeals board. (b) The administrative director or his or her designees, upon the submission of a matter to an information and assistance officer, may, upon the agreement of a party to pay the cost, and with the consent of an unrepresented employee direct the injured employee to be examined by a qualified medical evaluator selected by the medical director, within the scope of the qualified medical evaluator’s professional training, upon any clinical question, other than those issues specified in Section 4061, then pertinent to the investigation of the information and assistance officer. (c) The 1989 and 1990 amendments to this section shall become operative for injuries occurring on and after January 1, 1991.