Mass. Gen. Laws ch. 231 § 108
There shall be an appellate division of each district court for the rehearing of matters of law arising in civil cases, in claims of compensation of victims of violent crimes, and in civil motor vehicle infractions. The division of the Boston municipal court shall consist of 3 justices to be designated from time to time by the chief justice therefor. The appellate division of each other municipal court shall be holden by justices for the other divisions of the Boston municipal court department, included in the jurisdiction of the central division, East Boston court, Charlestown court, Brighton court, Dorchester court, Roxbury court, South Boston court, West Roxbury court, which shall be known as the appellate division of the Boston municipal court department. The appellate division of each other district court shall be holden by justices for those other district courts, not exceeding 3 in number out of 5 justices assigned to the performance of appellate duty by the chief justice for the district courts, subject to the approval of the chief justice of the supreme judicial court, as follows: The chief justice for the district courts shall assign 5 justices of districts within the counties of Essex and Middlesex and that part of Suffolk included in the jurisdiction of the district court of Chelsea to act in the appellate divisions of the district courts within those counties and that part of Suffolk county, which shall be known as the northern appellate division district; shall assign 5 justices of the district courts within the counties of Norfolk, Plymouth, Barnstable, Bristol, Dukes and Nantucket to act in the appellate divisions of the district courts within those counties, which shall be known as the southern appellate division district; and shall assign 5 justices of district courts within the counties of Worcester, Franklin, Hampshire, Hampden and Berkshire to act in the appellate divisions of district courts within those counties, which shall be known as the western appellate division district. The assignment may be made for the period of time as the chief justice considers advisable. In each of the foregoing 3 districts, 1 of the justices so assigned shall be designated by the chief justice for the district courts, subject to the approval of the chief justice of the supreme judicial court, as presiding justice, who shall from time to time designate those of the appellate justices who shall act on appeals in each district court in that district and direct the times and places of sittings. The presiding justice of any appellate division may call upon a justice of any other appellate division to serve in his division, and when so requested that justice shall serve therein. Two justices shall constitute a quorum to decide all matters in an appellate division; but each appellate division justice may sit as a single justice of the appellate division for the purpose of hearing and deciding appeals of interlocutory orders, as provided in section 118A of chapter 231.
A justice acting in the appellate division of a district court shall be allowed, in addition to his salary and necessary traveling expenses, incidental expenses and clerical assistance while so acting, which shall be paid by the commonwealth.
Any party to a cause brought in the municipal court of the city of Boston, or in any district court, aggrieved by any ruling on a matter of law by a trial court justice, may as of right, appeal the ruling for determination by the appellate division pursuant to the applicable rules of court. The justice whose ruling is appealed shall not sit upon the review thereof. If the appellate division shall decide that there has been prejudicial error in the ruling complained of, it may reverse, vacate or modify the same or order a new trial in whole or part; otherwise it shall dismiss appeal and may impose double costs in the action if it finds the objection to such ruling to be frivolous or intended for delay. If the party claiming the appeal shall not duly prosecute the same, by preparing the necessary papers or otherwise, the appellate division may order the cause to proceed as though no appeal had been filed and may in like manner impose costs. A trial court justice may, after decision thereon, report for determination by the appellate division any case in which there is an agreed statement of facts or a finding of the facts or any other case involving questions of law only. If a trial justice is of opinion that an interlocutory finding or order made by him ought to be reviewed by the appellate division before any further proceedings in the trial court, he may report the case for that purpose and stay all further proceedings except as necessary to preserve the rights of the parties. The municipal court of the city of Boston shall make rules regulating the procedure and sittings of the appellate division of the court, for appeal thereto, for the preparation and submission of reports and allowance of reports which a trial court justice shall disallow as not conformable to the facts or shall fail to allow by reason of physical or mental disability, death or resignation, for the reporting of cases reserved for report when a trial court justice shall fail to report the same by reason of physical or mental disability, death, resignation, removal or retirement, and for the granting of new trials.
Mass. Gen. Laws ch. 231, § 108