In Massachusetts towns that govern themselves by town meeting, the meeting is run by an elected moderator. State law says: “The moderator shall preside and regulate the proceedings, decide all questions of order, and make public declaration of all votes.”
“No person shall address a town meeting without leave of the moderator.” A person who keeps disturbing the meeting and refuses to leave can be removed by a constable or anyone the moderator orders, and held “in some convenient place until the meeting is adjourned.”