Mass. Gen. Laws ch. 175, § 94K

An advisory committee or other similar committee or board, composed of not less than three subscribers, shall be elected or appointed by each exchange in the manner provided by the power of attorney, which committee or board shall have the authority and duties provided therein. Notwithstanding the provisions of any general or special law to the contrary, no member of the advisory committee shall be subject to an action for libel or slander arising out of the conduct of such member in the reasonable performance of his duties.