Any person subject to this Act who commits any of the following offences, that is to say,--
         (a) unnecessarily detains a person in arrest or confinement without bringing him to trial, or fails to bring his case before the proper authority for investigation; or
         (b) having committed a person to air force custody fails without reasonable cause to deliver at the time of such committal, or as soon as practicable, and in any case within forty-eight hours thereafter, to the officer or other person into whose custody the person arrested is committed, an account in writing signed by himself of the offence with which the person so committed is charged;
shall, on conviction by court-martial, be liable to suffer imprisonment for a term which may extend to two years or such less punishment as is in this Act mentioned.