Mass. Gen. Laws ch. 218 § 81
A justice of a division of the district court department upon certificate of the chief justice for the district court department shall quarterly be reimbursed by the commonwealth for the traveling expenses incurred by him when sitting at the order of said chief justice in a division other than the division to which he was appointed.
If sessions of a division of the district court department are held in more than one town in its district, the chief justice of the district court shall designate in which town the clerk's main office shall be established, and the justices, clerk, assistant clerks, court officers and probation officers of such division shall each be allowed by the commonwealth traveling expenses necessarily incurred when required to hold or attend sessions of said division at any town in the district other than the town in which said main office is so established, such expenses to be computed either from the town where such office is established to such other town, or from his place of residence within such district to such other town, whichever is the shorter distance; provided, however, that a justice or a special justice appointed to the district court in Dukes county or the district court in Nantucket county shall receive his actual expenses for travel by land, sea or air from his residence on the mainland to such county office.
Mass. Gen. Laws ch. 218, § 81