Full Breakdown
Supreme Court Upholds Michigan's Lawsuit Against Enbridge's Line 5 Pipeline
4/23/2026, 9:09:06 PM
Legal Ruling on Jurisdiction
On April 22, 2026, the U.S. Supreme Court ruled unanimously in favor of Michigan, allowing the state's lawsuit against Enbridge Energy regarding the Line 5 pipeline to remain in state court. Justice Sonia Sotomayor stated that Enbridge missed a critical 30-day deadline to move the case to federal court, thus affirming the jurisdiction of Ingham County Circuit Court. The lawsuit, initiated by Michigan Attorney General Dana Nessel in June 2019, seeks to void the easement that permits Enbridge to operate a 4.5-mile section of the pipeline beneath the Straits of Mackinac, which connects Lake Michigan and Lake Huron.
Background of the Pipeline Dispute
Line 5 has been operational since 1953, transporting crude oil and natural gas liquids between Superior, Wisconsin, and Sarnia, Ontario. Concerns regarding the pipeline's safety have escalated since 2017, when Enbridge disclosed that it had known about gaps in the protective coating of the underwater section since 2014. An incident in 2018, where a boat anchor damaged the pipeline, intensified fears of a potential catastrophic spill in the Great Lakes.
In June 2020, Nessel secured a restraining order to temporarily halt operations, although Enbridge continued to operate after meeting specific safety requirements. Enbridge attempted to shift the case to federal court in 2021, arguing that the lawsuit involved U.S. and Canadian trade implications. However, the 6th U.S. Circuit Court of Appeals ruled in June 2024 that the company had missed the jurisdictional deadline, sending the case back to state court.
Ongoing Legal Challenges
The Supreme Court's ruling is part of a broader legal landscape surrounding Line 5. In addition to Nessel's lawsuit, Michigan Governor Gretchen Whitmer's administration revoked the pipeline's easement in 2020, a decision currently being challenged in federal court by Enbridge. A federal judge had previously blocked Whitmer's revocation attempt, asserting that federal regulators, specifically the Pipeline and Hazardous Materials Safety Administration (PHMSA), hold authority over pipeline safety.
Enbridge is also seeking permits to encase the underwater section of Line 5 in a protective tunnel, a project that received state approval in 2023 but still requires federal clearance from the U.S. Army Corps of Engineers and the Michigan Department of Environment, Great Lakes and Energy. Environmental groups and Michigan tribes have filed lawsuits to contest these state permits.
Criticism and Opposition
Critics, including environmental organizations and tribal groups, argue that the pipeline poses an unacceptable risk to the Great Lakes ecosystem. They contend that the potential for a spill could have devastating consequences for the region's water supply and wildlife. Enbridge maintains that the pipeline is safe and that federal inspections have consistently found it in compliance with safety standards.
What's Next
The legal battle over Line 5 continues, with Michigan appealing the federal ruling that blocked the state's easement revocation. Additionally, Enbridge faces a separate legal dispute in Wisconsin, where a federal judge has mandated the shutdown of a segment of the pipeline running through the Bad River Band of Lake Superior’s reservation unless it can be rerouted. Enbridge has begun work on a reroute while appealing the shutdown order.
Verbatim Quotes
- “Enbridge waited too long to remove this case to federal court,” — Justice Sonia Sotomayor, U.S. Supreme Court
- “The fact remains that the safety of Line 5 is regulated exclusively by the Pipeline and Hazardous Materials Safety Administration (PHMSA).” — Enbridge Statement
