The Maine Supreme Court will hear arguments in two cases on a proposed electricity transmission line from Canada to New England. The line is sponsored by Hyrdo-Québec and Avangrid (the owner of Central Maine Power Company). They are challenging a November referendum that rejected the project. The companies argue that the referendum is unconstitutional because the project had received the necessary approvals from both state and federal authorities prior to it being held. The second case concerns a 1-mile part of the route that is leased from the state. The challenge to the project rests upon a requirement that any “substantial alteration” of public lands must be approved by two-thirds of the members of the legislature, which was not done in this case.