N.H. Rev. Stat. § 111:2
Such military forces shall be composed of commissioned officers and such able-bodied citizens of the state as shall volunteer for service therein, supplemented, if necessary, by the unorganized militia enrolled by draft and subject to military duty as provided by RSA 110-B and, in addition to active units, may include inactive and reserve components. No person shall be appointed or enlisted in the state guard who is a member of any other military force of the United States or the state of New Hampshire, or who has any service obligation to any of the armed forces of the United States, except that a retired military member may be appointed or enlisted in the state guard, if otherwise qualified.
RSA 111:2
1941, 46:2. RL 144:2. RSA 111:2. 1975, 14:4. 1981, 327:2. 1985, 144:4, eff. July 19, 1985.