Defendants in City & County of Honolulu v. Sunoco LP filed two petitions for a writ of certiorari requesting the U.S. Supreme Court decide whether Honolulu can pursue its state law climate claims against energy manufacturers. The key question is whether federal law, under the constitutional structure of American federalism and the Clean Air Act, precludes state-law claims seeking redress for injuries allegedly caused by the effects of interstate and international greenhouse gas emissions on the global climate. In short: does liability over international emissions fall beyond the limits of any state law?
The petitions, here and here, ask the Court to review and, ultimately, overturn the Hawaii Supreme Court’s ruling in Honolulu’s case, which it issued in October 2023. That court held that its courts can apply Hawaii state law to emissions and conduct occurring entirely outside of Hawaii. In doing so, it failed to distinguish between the interstate and international aspects of the claims.
The Hawaii ruling, as the companies’ petitions point out, is in direct conflict with a decision by the U.S. Court of Appeals for the Second Circuit. In 2021, the Second Circuit dismissed a comparable climate lawsuit brought by New York City that also sought to subject energy manufacturers to liability for climate change. The Second Circuit explained that climate change and its impacts in any given region is the result of global emissions over the past 150 years and are “beyond the limits of state law.”
As MAP Special Counsel Phil Goldberg pointed out in a statement supporting the petitions, “The Supreme Court found in AEP v. Connecticut that claims relating to global fuel emissions raise issues ‘of special federal interest’ and that ‘borrowing the law of a particular state would be inappropriate.’” As the Second Circuit explained, today’s climate cases are no different.
Indeed, in January, the Delaware Superior Court significantly narrowed the scope of Delaware’s climate lawsuit for these reasons. It held that Delaware law cannot apply to emissions that occurred in other states or around the world: “The Court finds that claims in this case seeking damages for injuries resulting from out-of-state global greenhouses emissions and interstate pollution, are preempted by the [Clean Air Act]. Thus, these claims are beyond the limits of Delaware common law.” Rather, the state can sue only over emissions originating in Delaware.
The potential for additional conflicting rulings continues to grow, as motions to dismiss similar cases are pending in several other state courts, including Maryland, New Jersey, Rhode Island, and Vermont. And lawsuits have been filed in nearly 30 jurisdictions, as this entire litigation is the result of a campaign to encourage lawsuits that attempt to circumvent Congress and federal agencies on climate policy.
The Supreme Court should take up the petitions now and provide clarity on these important and recurring legal issues. Otherwise, it risks the creation of a patchwork of ad hoc case-by-case rulings that will reach different outcomes and effectively set America’s energy policy—an outcome the Court specifically warned against in AEP vs. Connecticut more than a decade ago.