The court, or judge thereof, in conducting such hearing, shall have all the usual powers of the circuit court or judge, including the power to subpoena and examine witnesses of its own motion. The Governor, the officer affected or any party interested may subpoena witnesses and appear and participate in person or by counsel, and the officer shall be given reasonable opportunity to prepare and present this case. The Attorney General shall appear on behalf of the Governor if by the Governor requested so to do.