12. At the hearing of any proceedings before a Tribunal—
(a)a party other than the Revenue may be represented by any person whether or not legally qualified, except that if in a particular case the Tribunal is satisfied that there are good and sufficient reasons for doing so, it may refuse to permit a particular person, other than one who is legally qualified or who has been admitted a member of an incorporated society of accountants, to represent a party at the hearing;
(b)the Revenue may be represented by a barrister, advocate, solicitor or any officer of the Board.