Mass. Gen. Laws ch. 49, § 8: Remedy for repairing more than just share of partition fence

Section 8. If a partition fence is required under this chapter between the lands of adjoining occupants, and either of them has, before complaint made, voluntarily erected the whole fence or more than his just share thereof, or has otherwise become proprietor thereof, the fence viewers may order the other occupant to pay the value of so much thereof as may be assigned to him to repair or maintain, to be ascertained and recovered as provided in this chapter.