23. —(1) An investigation by the Commissioner under this Act shall be conducted otherwise than in public.

(2) Where the Commissioner proposes to carry out an investigation under this Act he or she shall—

(a) notify—

(i) the public body concerned,

(ii) in a case where a complaint has been made to the Commissioner, the person who made the complaint, and

(iii) the Minister,

in writing of that fact, and

(b) afford—

(i) the public body concerned, and

(ii) any other person who appears or, in a case where a complaint has been made to the Commissioner, is alleged to have been responsible for the matter complained of,

an opportunity to comment on the matter and, if a complaint in relation to the matter has been made to the Commissioner, on any allegations contained in the complaint.

(3) The Commissioner may—

(a) refuse to investigate a complaint under this Act, or

(b) discontinue an investigation under this Act into such a complaint,

if he or she becomes of opinion that—

(i) the complaint is trivial or vexatious,

(ii) the person making the complaint has not taken reasonable steps to seek redress in respect of the subject matter of the complaint or, if he or she has, has not been refused redress,

(iii) the complaint relates solely to a matter within the power of the Ombudsman to investigate pursuant to section 4(2)(a) of the Ombudsman Act 1980, or

(iv) the matter complained of does not involve any contravention of the provisions of this Act or of any other enactment relating to the status or use of an official language.

(4) Subject to the provisions of this Act, the procedure for conducting an investigation shall be such as the Commissioner considers appropriate in all the circumstances of the case.

(5) The Commissioner may determine whether any person may be represented, by counsel, solicitor or otherwise, in an investigation by him or her under this Act.