Me. Rev. Stat. tit. 14, § 703

A constable may serve, execute and return upon any person in his town or in an adjoining plantation any writ of forcible entry and detainer, or any precept in a personal action, including those in which a town, plantation, parish, religious society or school district of which he is a member is a party or interested, but before he serves any process, he shall give bond to the inhabitants of his town in the sum of $500, with 2 sureties approved by the municipal officers thereof, who shall indorse their approval on said bond in their own hands, for the faithful performance of the duties of his office as to all processes by him served or executed. For every process that he serves before giving such bond, he forfeits not less than $20 nor more than $50 to the prosecutor.