Any person violating this act shall be a competent witness and compellable to testify in any proceeding under sections 172 and 173 of this act against any other person charged with so offending, but the testimony of the former person given in any such case shall not be used in any prosecution, civil or criminal, against the person so testifying except for perjury committed by him while so testifying.
N.J.S. § 17:12B-175