(1) Where one Commissioner only stands appointed for the time being under section 15, the Minister may authorise a member of staff of the Commission to perform the functions of a Commissioner during any period when that Commissioner is absent from duty or absent from the State or is, for any other reason, unable to perform the functions of a Commissioner.
(2) Where a vacancy occurs in the office of Commissioner and no Commissioner stands appointed for the time being under section 15, the Minister may authorise a member of staff of the Commission to perform the functions of a Commissioner during the period of that vacancy, but an authorisation under this subsection shall cease upon the appointment of a Commissioner under section 15 whether or not such appointment was made for the purpose of filling that vacancy.
(3) An authorisation under subsection (2) shall not remain in force for a period of more than 6 months unless the Minister is satisfied that it is not reasonably practicable for
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