The Commission may order any person to answer a question or questions or produce evidence of any kind and confer immunity as provided in this section. If, in the course of any investigation or hearing conducted under this chapter, a person refuses to answer a question or produce evidence on the grounds that he will be exposed to criminal prosecution thereby, then in addition to any other remedies or sanctions provided for by this chapter, the Commission may, by resolution of six of its members and after the written approval of the Attorney General, issue an order to answer or to produce evidence with immunity. If upon issuance of such an order, the person complies therewith, he shall be immune from having such responsive answer given by him or such responsive evidence produced by him, or evidence derived therefrom, used to expose him to criminal prosecution, except that such person may nevertheless be prosecuted for any perjury committed in such answer or in producing such evidence, or for contempt for failing to give an answer or produce evidence in accordance with the order of the Commission; provided, however, that no period of incarceration for contempt shall exceed 180 days in duration pursuant to this section. Any such answer given or evidence produced shall be admissible against him upon any criminal investigation, proceeding or trial against him for such perjury; upon any investigation, proceeding or trial against him for such contempt; or in any manner consonant with territorial and constitutional provisions.