(a) A party may file a motion to conduct discovery with the administrative law judge. The motion for discovery shall be granted by the administrative law judge only upon a showing of good cause. In order to establish “good cause” for the purposes of this section, a party must show that the discovery requested relates to a genuine issue as to a material fact that is relevant to the proceeding. The order of the administrative law judge shall expressly limit the scope and terms of discovery to that for which “good cause” has been shown, as provided in this paragraph.

(b) A party may obtain discovery of documents and tangible things otherwise discoverable under paragraph (a) of this section and prepared in anticipation of or for the hearing by or for another party's representative (including his or her attorney, consultant, surety, indemnitor, insurer, or agent) only upon showing that the party seeking discovery has substantial need of the materials or information in the preparation of his or her case and that he or she is unable without undue hardship to obtain the substantial equivalent of the materials or information by other means. In ordering discovery of such materials when the required showing has been made, the administrative law judge shall protect against disclosure of the mental impressions, conclusions, opinions, or legal theories of an attorney or other representatives of a party concerning the proceeding.