(a) Appearances generally. Representation of parties in proceedings before Appeals Boards of the Office of Hearings and Appeals is governed by Part 1 of this subtitle, which regulates practice before the Department of the Interior.

(b) Representation of the Government. Department counsel designated by the Solicitor of the Department to represent agencies, bureaus, and offices of the Department of the Interior in proceedings before the Office of Hearings and Appeals, and Government counsel for other agencies, bureaus or offices of the Federal Government involved in any proceeding before the Office of Hearings and Appeals, shall represent the Government agency in the same manner as a private advocate represents a client.

(c) Appearances as amicus curiae. Any person desiring to appear as amicus curiae in any proceeding shall make timely request stating the grounds for such request. Permission to appear, if granted, will be for such purposes as established by the Director or the Appeals Board in the proceeding.