Me. Rev. Stat. tit. 1, § 21 (2025)
The county commissioners shall file in the office of the clerk of the Superior Court a report of their doings, which is conclusive upon the parties unless one of them within 30 days files in court a motion for a new trial, which after due notice to the opposite party may for due cause be granted, to be had in that court.
RR 2023, c. 1, Pt. C, §3 (COR).