Mass. Gen. Laws ch. 41, § 122

Unless otherwise provided by law, if the office of treasurer of a district is vacant, or if the treasurer is absent, or unable to perform his duties because of disability, the prudential committee, if any, otherwise the commissioners, may appoint a temporary treasurer to hold such office and exercise the powers and perform the duties thereof until another is duly elected or appointed and qualifies according to law or until the treasurer who was disabled or absent resumes his duties. Any such temporary treasurer shall be sworn to and give bond for the faithful performance of his duties in accordance with the provisions of law applicable to the treasurer whose position he fills, and if he fails so to do within ten days after his appointment, the prudential committee, if any, otherwise the commissioners, shall rescind the appointment and appoint another.