Section 22. (a) Whenever necessary, there shall be a military service commission, hereinafter referred to in this section as the commission, consisting of the adjutant general and 6 officers of the Massachusetts national guard, army and air; provided, however, that 3 of such officers shall be selected from the army national guard and 3 of such officers shall be selected from the air national guard. The commander-in-chief shall initially detail 2 such officers for terms of 1 year each, 2 such officers for terms of 2 years each and 2 such officers for terms of 3 years each. Thereafter all officers shall be detailed to the commission for terms of 3 years by the commander-in-chief.
(b) Subject to Article LIII of the Articles of Amendment of the Constitution, a person certified as eligible for any specific grade in the national guard, army or air under the laws of the United States and who is a graduate of the Massachusetts Military Academy shall be eligible for appointment without professional examination.