Judge Ellen A. Gorman of the Maine Supreme Judicial Court listens to arguments during an appeal in this 2013 file photo. Credit: Troy R. Bennett / BDN

Maine’s high court wrestled on Wednesday with arguments in a lawsuit aiming to stop a November vote on a question aiming to kill Central Maine Power’s controversial hydropower corridor proposal that could have major implications for the project’s path.

At stake is more than the $1 billion project and a high-dollar campaign being waged against the possibly unconstitutional referendum by CMP and Hydro-Quebec, the province-owned utility. The case tests the power of Mainers to overrule state regulators and the Maine Supreme Judicial Court’s typical unwillingness to wade into political disputes during an election.

Avangrid, CMP’s parent company, filed a lawsuit in May against Secretary of State Matt Dunlap, seeking to stop his office from putting the question to kill the corridor proposal on the 2020 ballot, arguing that it violates a separation of powers provision in the Maine Constitution.

A judge ruled against the utility in June, agreeing with Dunlap’s assertion that while the referendum may be unconstitutional, it was not necessary to determine that ahead of an election in which the question may pass or not. Avangrid appealed that ruling to the high court.

Even if the referendum is not binding, it could serve as a powerful rebuke of the project that corridor opponents could leverage in the Legislature to lobby for constitutional or other legal fixes, as has happened with ranked-choice voting and an offshore wind energy project involving the University of Maine and CMP.

In oral arguments on Wednesday before the Maine Supreme Judicial Court, Avangrid attorney John Aromando said that choosing to not weigh in on the question prior to the November election would be a failure on the court’s part. He implored judges not to take “cede an important constitutional function of the judiciary to the legislative branch.”

“It is impossible to overstate how important it is for this court to decline that invitation,” he said.

Judges, however, questioned why the courts should take away people’s right to vote on a measure aiming to compel the Legislature to act. They also probed how Dunlap’s office could allow the question to go forward even if he thought it was unconstitutional.

“Wouldn’t that demonstrate disrespect for the voters of Maine to put onto a ballot something that could not be enacted, even if they voted on it?” Justice Ellen A. Gorman asked.

She then asked if the question could go forward if the court decided it was unconstitutional. Assistant Maine Attorney General Phyllis Gardiner replied that the question was complicated by the timing of Avangrid’s objection to the question, which came after the high court upheld Dunlap’s ruling that the question had enough signatures to get on the ballot.

Gardiner said the question would be placed on the ballot if the courts found the question non-binding, but that the office would follow any court ruling that the proposed law is unconstitutional by removing it from the ballot.

“We think what’s crucially important is that people have an understanding as to their power before something is presented to them, if it is presented, on the ballot,” she said.