The U.S. Supreme Court recently refused to hear a lawsuit by an Alaskan village accusing Exxon Mobil and other energy companies of making the area uninhabitable by releasing greenhouse gas emissions that have contributed to global warming. The Ninth Circuit had previously rejected the suit, relying heavily on the Supreme Court’s 2011 decision in American Electric Power Co. Inc. v. Connecticut. The court had ruled then that the Clean Air Act and the U.S. Environmental Protection Agency’s authority displace federal common law emissions claims.

According to Mike McDonough, an environmental partner in Pillsbury’s Los Angeles office, the AEP decision “laid down the gauntlet— the CAA is one-stop shopping for questions under climate change.”

“I think the prevailing thought out there is that the door is basically shut on the federal side for both injunctive relief and monetary relief,” he said.

“The nature of climate change, unlike other pollution, [is that] it doesn't matter where the pound of emissions comes from,” McDonough stated. “It's sort of the luck of the draw as to who [plaintiffs] choose to sue.” For example, he asked, if you sued oil refineries in your area for causing global warming with their greenhouse gas emissions, why not area chemical or manufacturing plants as well? If you're targeting all greenhouse gas-emitting entities in your state, what about entities in neighboring states?

Discussing the difficulty of enforcing any climate change standard, McDonough added, “You could end up with a hodgepodge of decisions throughout the country about what constitutes a nuisance, what emission levels are injurious enough to be actionable, and causation. It would be almost unmanageable to harmonize those decisions.”