21.—(1) At any hearing by the Tribunal, other than a hearing under rule 11 above–
(a)a party may, subject to rules 17(2) above and 23(3) below, conduct his case himself or may appear and be represented by any person whom he may appoint for the purpose, and
(b)the relevant Minister may appear and be represented by any person whom he may appoint for the purpose.
(2) At any hearing by the Tribunal under rule 11(5) above, the appellant may conduct his case himself or may appear and be represented by any person whom he may appoint for the purpose.