Mass. Gen. Laws ch. 8 § 10
Rooms shall only be assigned to or used by either branch of the general court or any committees or officers thereof, except with the written consent of the presiding officer of the branch using such rooms, or to rooms assigned to or used by joint committees of the general court, except with the written consent of the presiding officers of both branches of the general court, nor shall it apply to the rooms used by the Grand Army of the Republic of the department of Massachusetts under section seventeen, except with the consent of the commander thereof. The commissioner of administration shall, during the sessions of the general court, upon application of the sergeant-at-arms subject to such rules as the committee on rules of the two branches acting concurrently may adopt, assign such rooms as may be required for the use of committees and other purposes.
Mass. Gen. Laws ch. 8, § 10