(Photo: CBS)
Michigan / Great Lakes Region — April 23, 2026
Michigan’s long-running legal fight over the Enbridge Line 5 pipeline entered a new phase Thursday following a unanimous U.S. Supreme Court decision that keeps the case in state court, removing a key procedural challenge raised by the Canadian energy company.
The ruling, issued Wednesday, rejected Enbridge’s argument that Michigan’s 2019 lawsuit should be moved to federal court. Justice Sonia Sotomayor wrote for the Court that the company waited too long—well beyond the 30-day removal deadline—to request the jurisdictional change.
The decision allows Michigan Attorney General Dana Nessel’s lawsuit to proceed in state court, where it seeks to shut down or restrict operations of the 645-mile pipeline that carries oil and natural gas liquids between Wisconsin and Ontario through the Straits of Mackinac.
The pipeline, operated by Enbridge, has been at the center of environmental and legal disputes for years due to concerns over its aging infrastructure and the potential risk of a spill in the Great Lakes.
Michigan officials have argued that the section of Line 5 running beneath the Straits poses an unacceptable risk to the region’s freshwater system, while Enbridge maintains that the pipeline is safe, essential to regional energy supply, and subject to extensive monitoring and federal oversight.
The Supreme Court decision does not rule on whether the pipeline must be shut down, but it significantly narrows Enbridge’s legal strategy by eliminating its bid to move the case into a potentially more favorable federal venue.
Legal experts say the ruling accelerates pressure on both sides as the case returns to Michigan courts for substantive proceedings that could determine the pipeline’s long-term future.
The case remains one of the most consequential environmental and energy disputes in the Great Lakes region, with implications for cross-border infrastructure, state environmental authority, and Midwest fuel supply chains.