Accused person to be a competent witness

(1) Any person charged with an offence punishable under this Act, shall be a competent witness for the defence and may give evidence on oath in disproof of the charges made against him or any person charged together with him at the same trial: Provided that- (a) he shall not be called as a witness except at his own request; (b) his failure to give evidence shall not be made the subject of any comment by the prosecution or give rise to any presumption against himself or any person charged together with him at the same trial;