54.—(1) A Minister of the Crown (whether or not he is a party to the proceedings) may, if he considers it expedient in the interests of national security, direct a tribunal or chairman by notice to the Secretary to:—
(a)conduct proceedings in private for all or part of particular Crown employment proceedings;
(b)exclude the claimant from all or part of particular Crown employment proceedings;
(c)exclude the claimant’s representative from all or part of particular Crown employment proceedings;
(d)take steps to conceal the identity of a particular witness in particular Crown employment proceedings.
(2) A tribunal or chairman may, if it or he considers it expedient in the interests of national security, by order —
(a)do anything which can be required by direction to be done under paragraph (1);
(b)order any person to whom any document (including any judgment or record of the proceedings) has been provided for the purposes of the proceedings not to disclose any such document or the content thereof:–
(i)to any excluded person;
(ii)in any case in which a direction has been given under paragraph (1)(a) or an order has been made under paragraph (2)(a) read with paragraph (1)(a), to any person excluded from all or part of the proceedings by virtue of such direction or order; or
(iii)in any case in which a Minister of the Crown has informed the Secretary in accordance with paragraph (3) that he wishes to address the tribunal or chairman with a view to an order being made under paragraph (2)(a) read with paragraph (1)(b) or (c), to any person who may be excluded from all or part of the proceedings by virtue of such an order, if an order is made, at any time before the tribunal or chairman decides whether or not to make such an order;
(c)take steps to keep secret all or part of the reasons for its judgment.
The tribunal or chairman (as the case may be) shall keep under review any order it or he has made under this paragraph.
(3) In any proceedings in which a Minister of the Crown considers that it would be appropriate for a tribunal or chairman to make an order as referred to in paragraph (2), he shall (whether or not he is a party to the proceedings) be entitled to appear before and to address the tribunal or chairman thereon. The Minister shall inform the Secretary by notice that he wishes to address the tribunal or chairman and the Secretary shall copy the notice to the parties.
(4) When exercising its or his functions, a tribunal or chairman shall ensure that information is not disclosed contrary to the interests of national security.