(a) The Assistant Secretary may designate a presiding official to conduct any stage of the proceeding, including officiating at a conference, oral presentation, or trial-type hearing. The presiding official shall have the full authority of the Assistant Secretary during such proceedings.

(b) A presiding official at a conference, oral presentation, or trial-type hearing shall have the authority to regulate the conduct of the proceeding including, but not limited to, determination of the issues to be raised during the course of the conference, oral presentation, or trial-type hearing, administering oaths or affirmations, directing discovery, ruling on objections to the presentation of testimony or exhibits, receiving relevant and material evidence, requiring the advance submission of written testimony and exhibits, ruling on motions, determining the format, directing that briefs be filed with respect to issues raised or to be raised during the course of the conference, oral presentation or trial-type hearing, questioning witnesses, taking reasonable measures to exclude duplicative material, and placing limitations on the number of witnesses to be called by a party.