The U.S. Supreme Court heard arguments on Tuesday about whether state or federal court will have the final say on the future of the controversial Line 5 pipeline, which carries crude oil and natural gas liquids across the Straits of Mackinac in Michigan.
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The case dates to a 2019 lawsuit by Michigan Attorney General Dana Nessel, who moved to shut down the pipeline by revoking the easement that allows it to cross the Straits, citing risks to the Great Lakes. (Over its 73-year lifetime, Line 5 has spilled over a million gallons of oil along its inland route.) A shutdown is supported by all 12 federally recognized tribes in Michigan, though they are not involved in the suit. Many tribal nations say the pipeline threatens their waters, treaty rights, and ways of life.
On Tuesday, the justices asked tough questions of both the attorney general’s team as well as lawyers representing the Canadian pipeline company, Enbridge Energy, on the opposing side. Though the question before the Supreme Court is a procedural one — whether courts can excuse Enbridge from missing the deadline to request moving the case to federal court — the justices recognized that the decision could have far-reaching ripples, including for U.S.-Canada relations. (The Canadian government opposes the pipeline’s shutdown, as Line 5 provides half of the oil supply for Ontario and Quebec.)
“If this proceeds in state court, and the state court issues a preliminary injunction against continued operation of the pipeline, it could be a long time before this issue involving treaty rights, which is a federal question, could be reviewed here,” noted Justice Samuel Alito.
Since 1953, Line 5 has transported oil and natural gas liquids 645 miles from Superior, Wisconsin, to Sarnia, Ontario — with a critical 4-and-a-half-mile segment along the bottomlands in the Straits between Lakes Huron and Michigan. Enbridge wants to move the case to the federal court, which the company argues is better suited to weigh in on federal pipeline safety regulations and international agreements.
On the opposing side, Nessel argues that Line 5 belongs in state court because the pipeline concerns state laws around the use of natural resources for the good of the public. Nessel and anti-pipeline groups worry about the environmental, economic, and health consequences of an oil spill in the Great Lakes.
Ryan Duffy, a spokesperson for Enbridge, said in a statement before the oral arguments that there would be “significant implications for energy security and foreign affairs if the Attorney General continues to pursue the lawsuit now in state court.”
Enbridge first argued that the case should be moved to federal court in 2021, sparking litigation around whether the company had missed the typical 30-day deadline to change venues. A federal district court judge in western Michigan ruled in favor of Enbridge due to “exceptional circumstances” around related lawsuits involving the pipeline. However, later the U.S. Sixth Circuit Court ruled in favor of the state.
On Tuesday, Enbridge lawyer John Bursch compared the deadline to a statute of limitations and argued that exceptional circumstances could justify an extension.
“I don’t think it was clear to anyone that there was necessarily federal jurisdiction at the outset of the state court case,” Bursch said.
Ann Sherman, a lawyer representing the state attorney general, argued that the 30-day deadline is a firm rule on court venue, unlike the statute of limitations. “Enbridge seeks an atextual escape hatch,” she said.
A decision from the Supreme Court on Line 5’s jurisdiction is expected before the court term ends in summer. If the court rules in favor of Michigan, it would uphold the Sixth Circuit’s decision that Enbridge missed the deadline and make Line 5 an issue for state court, said Andy Buchsbaum, a lecturer at the University of Michigan Law School.
However, “if the court decides that there is wiggle room in the 30-day deadline, there’s lots of ways this could go,” he said. The justices would likely settle on a standard allowing the deadline to be excused. From there, they could ask the Sixth Circuit to reevaluate the facts of the case with the new standard in mind, as Enbridge’s lawyer argued before the Supreme Court. Or the justices could apply their own standard and come to a decision for or against the state.
“To know what’s at stake and hear the court considering that just on a procedural basis, gives me a lot of concerns,” said Whitney Gravelle, president of the Bay Mills Indian Community, after oral arguments. The tribal nation in Michigan’s Upper Peninsula is involved in separate litigation against Line 5.
“Line 5 continues to remain a clear and present danger to the Great Lakes and every tribal nation in every community that relies on them,” Gravelle said.
While the Supreme Court case plays out, Enbridge is moving ahead with plans to replace the existing dual-pipeline infrastructure in the Straits with a tunnel that would house a new segment buried under the lakebed. The company is awaiting permits from federal and state agencies. Separately, next month the Michigan Supreme Court will consider a lawsuit from tribes and environmental groups seeking to overturn an existing state permit.
Enbridge insists that Line 5 is safe and the tunnel project would make the pipeline segment even safer. Line 5 opponents like Liz Kirkwood, executive director of the Michigan-based legal nonprofit For Love of Water, disagree.
“We should be thinking about the future and the transition away from fossil fuel. And move towards a future that is sustainable and more equitable,” Kirkwood said.
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