A person may be represented by an attorney at law in any proceeding before the Director or Department, provided the attorney is admitted to practice before the highest court of any state or territory of the United States, or the Court of Appeals or the District Court of the United States for the District of Columbia. Alternatively, a person may appear before the Director or Department on his or her own behalf; a member of a partnership may represent the partnership; and an authorized officer of a corporation, trust or association may represent that corporation, trust or association.