TRAVERSE CITY, Mich. (AP) — The Michigan Court of Appeals ruled Thursday that legislators did not violate the state constitution by allowing construction of an oil pipeline tunnel beneath a channel linking two of the Great Lakes, clearing the way for the project to proceed unless another court intervenes.

A three-judge panel affirmed a ruling last November by the Michigan Court of Claims, which upheld a law authorizing a deal between former Republican Gov. Rick Snyder and Canadian pipeline company Enbridge.

They had negotiated a plan to drill the tunnel through bedrock beneath the Straits of Mackinac, which connects Lakes Michigan and Huron and divides Michigan’s upper and lower peninsulas.

It would house a pipeline that would replace a four-mile-long (six-kilometer-long) underwater segment of Enbridge’s Line 5, which carries crude oil and natural gas liquids used in propane between Superior, Wisconsin, and Sarnia, Ontario.

Lawmakers approved the agreement during a lame-duck session in December 2018 over objections that the measure was drafted sloppily and rushed to enactment before Democrat Gretchen Whitmer, who criticized the deal, took over for Snyder the following month.

“The handout to Enbridge allowed the company to avoid the normal vetting process of a project of this magnitude — cutting out public comment and input,” said Beth Wallace, conservation partnerships manager for the National Wildlife Federation’s Great Lakes office.

Snyder and Republican legislators said the deal was struck after years of public discussion.

Attorney General Dana Nessel, also a Democrat, issued an opinion in March 2019 that the authorizing bill was unconstitutional because its provisions far exceeded what its title specified.

Enbridge requested a ruling from the Court of Claims, where Judge Michael Kelly found that lawmakers had adequately followed the constitutional requirement to express a bill’s “general purpose or object” in its title.

Appeals judges Thomas Cameron, Mark Boonstra and Anica Letica — all appointed by Snyder — agreed.

“We conclude that the title … does not address objects so diverse that they have no necessary connection,” they said in a written opinion Thursday.

The ruling was a victory for Enbridge, which says it plans to finish the tunnel by 2024.