21.-(1) In the case of witnesses who are government officials, their costs shall be determined as follows:-
(a) if they are officials who are entitled to transport and subsistence allowances under the travelling regulations for the time being in force, they may be paid their costs as witnesses in accordance with such regulations;
(b) if they are officials who are not so entitled, they may, when attending a Court as witnesses outside their beat or division, be allowed costs at the rates for transport and subsistence laid down for officers in receipt of corresponding salaries. Medical officers entitled to private practice may in addition be allowed half a day’s salary in respect of each night’s absence from their beat or division.
(2) Every government official attending to give evidence shall be furnished by the Registrar of the Court with a certificate of attendance on such form as the Accountant-General may direct and be paid his costs on the ordinary form for a travelling claim, to which the Registrar’s certificate should be attached.