Me. Rev. Stat. tit. 30-A, § 3514

Charter service provided by the district must originate or terminate at some point within that district. Charter service provided by a district is in all respects subject to the jurisdiction of the Public Utilities Commission in the same manner and to the same extent as private companies providing charter service, except that a regional transportation corporation may not provide any charter service other than that specifically provided for under the conditions of any license granted the corporation by the Public Utilities Commission.