The U.S. Supreme Court recently agreed to determine whether a Colorado climate tort claim against Exxon Mobil Corp. and Suncor Energy Inc. can proceed in state court, a decision that may determine whether state efforts to impose climate liability are federally preempted.

The city and county of Boulder, Colo. filed suit against Exxon and Suncor in 2018 alleging that the two companies “knowingly contributed to climate change while concealing the dangers of their products.” The lawsuit seeks to hold the companies accountable for the costs associated with climate change that Boulder alleges would otherwise fall on taxpayers.

In response to Boulder’s lawsuit, Exxon and Suncor appealed to the Colorado Supreme Court, arguing that climate torts brought under state law are barred under the U.S. Constitution and the Clean Air Act and thus, the lawsuit should be dismissed. The court declined to dismiss the lawsuit, which resulted in an appeal to the U.S. Supreme Court by Exxon and Suncor.

According to Boulder Mayor Aaron Brockett, local communities bear the costs of climate change and these communities “have the right to hold companies accountable for out-of-state harms caused in-state.” The Boulder suit argues that oil companies should cover past and future costs incurred on the local level for steps taken to mitigate the effects of climate change, citing infrastructure repairs, environmental damage, emergency management, and harms to public health.

Exxon and Suncor, on the other hand, assert that climate policy should not be set through “fragmented state court decisions” — a position also supported by the Trump Administration. The companies argue that regulating interstate pollution “is an inherently federal area necessarily governed by federal law.”

Boulder is one of many state and local governments that have filed climate tort suits against fossil fuel companies. Until recently, the U.S. Supreme Court has rejected requests to hear similar appeals involving whether state courts have jurisdiction to hear climate tort claims.

Ultimately, the U.S. Supreme Court’s review of the Boulder lawsuit could impact the growing number of state climate tort suits. It is important to note, however,  that in granting Exxon and Suncor’s petition, the U.S. Supreme Court directed the parties to brief whether the justices even have authority to hear the case, which creates an opening for the court to potentially decline determining the petition on the merits – a move that some believe indicates a broader reluctance by the court to get involved in state-level tort litigation.

As a final note, the U.S. Environmental Protection Agency recently repealed a previous finding that greenhouse gasses endanger health, asserting that the EPA lacks the authority to regulate greenhouse gasses. Among the federal preemption arguments raised by Exxon and Suncor in the Boulder suit is the argument that the Clean Air Act preempts or otherwise displaces state law claims relating to greenhouse gases. The EPA’s recent recession on greenhouse gas emissions, however, may impact the preemption argument in state climate suits generally – that is, states may now be able to argue that federal preemption is irrelevant now that the EPA claims it lacks the authority to regulate greenhouse gasses.

Goldberg Segalla’s Environmental Law Monitor will continue to track the Boulder appeal, along with developments in state climate tort lawsuits.