Mass. Gen. Laws ch. 54 § 142
Upon failure to choose a district attorney, clerk of the courts or in Suffolk county of the supreme judicial or superior court, register of probate or sheriff, the governor shall cause precepts to be issued to the proper officers, directing them to call an election on the day appointed therein for the election of such officer.
Upon a vacancy by removal or otherwise in any of the above named offices, he shall in like manner cause precepts to be issued for an election to fill such vacancy at the next biennial state election for which precepts can be seasonably issued, unless the term of the office expires on the first Wednesday of January following such state election.
Upon a vacancy in the office of district attorney, register of probate or sheriff, the governor with the advice and consent of the council may appoint some person thereto until a district attorney, register of probate or sheriff is qualified.
Upon a vacancy in the office of clerk of the courts in any county, or of the clerk of the supreme judicial court in Suffolk county, the justices of said court may appoint a clerk to hold the office until a clerk is qualified.
Upon a vacancy in the office of a clerk of the superior court in Suffolk county, the justices of said court may appoint a clerk to hold the office until a clerk is qualified.
Mass. Gen. Laws ch. 54, § 142