Court Vacated a Key Permit for Enbridge Energy's Line 5 Tunnel Project, Ruling That State Regulators Failed to Assess the Full Environmental

In a 6-1 decision, justices sent the permit back to the Michigan Public Service Commission for broader review, likely delaying a project already tangled in legal battles. The court found the commission wrongly limited its analysis under the Michigan Environmental Protection Act to the tunnel alone, rather than the pipeline's wider effects. Justice Elizabeth Welch wrote that the commission overlooked potential harms and the public's right to use Great Lakes resources under the public trust doctrine.

The ruling requires the commission to determine whether the tunnel extends the 73-year-old pipeline's lifespan and what that means for the environment. Plaintiffs, including four tribal nations and three environmental groups, argued the project increases oil spill risks and greenhouse gas emissions. "The court has made clear that our understanding of environmental harm is practical but also broad, said Chad Hughes, senior attorney for the Environmental Law Policy Center.

Whitney Gravelle, president of the Bay Mills Indian Community, said the decision opens doors to discussing alternatives to Line 5. Enbridge spokesperson Ryan Duffy expressed disappointment, reaffirming the company's commitment to safe operations. Justice Brian Zahra dissented, calling the directive a "moral hazard, though he agreed on the public trust requirement. Line 5, which runs 645 miles from Wisconsin to Ontario, faces separate legal challenges, including from Governor Gretchen Whitmer's administration.