Efficiency and medical examining boards appointed by the Governor are vested with the powers of courts of inquiry and courts-martial. The boards shall follow the practice and procedure prescribed by applicable laws of the United States and the state and the regulations issued thereunder. Any officer ordered to appear before such a board shall be allowed to appear in person or by counsel, to cross-examine witnesses, and to call witnesses in his behalf. He shall at all stages of the proceeding be allowed full access to records pertinent to his case and be furnished with copies of the same. Failure to appear before any such examining board shall be sufficient ground for a finding by the board that the officer ordered to appear should be discharged. If the findings of the board are unfavorable to an officer and are approved as provided by applicable laws of the United States or by the Governor, the Governor shall relieve the officer from duty and shall give him a discharge in such form as may be appropriate; provided, however, that if the discharge of an officer is recommended solely because of physical inability to perform active service, the officer may be transferred to the state reserve list or the state retired list in accordance with this chapter.