9.—(1) Unless otherwise approved by the authorising officer —
(a)
no allowance or sum shall be allowed under regulation 3, 4, 5, 6, 7 or 8 in respect of a public officer required for an attendance in court as a witness to a matter of which he has acquired knowledge in the course of his duty; and
(b)
the relevant Instruction Manual or Government circulars relating to transport and travel shall apply to such a public officer.
(2) Where a public officer is required for an attendance in court as a witness to any other matter, regulation 8 shall apply to him; but no allowance or sum shall be allowed under regulation 3, 4, 5, 6 or 7 unless he suffers any loss of earnings or pay, which he would otherwise have received.