Colorado Supreme Court Hears Arguments in Climate Accountability Case

Colorado Supreme Court Hears Arguments in Climate Accountability Case

DENVER — On Tuesday, the Colorado Supreme Court heard oral arguments in an appeal by ExxonMobil and Suncor Energy. The companies are challenging a lower court ruling that has allowed the County of Boulder and the City of Boulder to pursue a lawsuit against them in state court. The action, filed in 2018, aims to hold the companies accountable for their contributions to the climate crisis and seeks financial compensation for the escalating costs of climate-related disasters. 

The lawsuit alleges that ExxonMobil and Suncor knowingly misled the public about the dangers of fossil fuels while continuing to contribute to climate change. Boulder County, the City of Boulder, and San Miguel County argue that these companies should help cover the costs of climate adaptation, which are increasingly falling on local governments and taxpayers.

Richard Herz, Chief Litigation Attorney at EarthRights International, emphasized Exxon’s longstanding knowledge of climate risks.

“Exxon has known for decades that human-caused climate alteration would have catastrophic effects, including in Colorado,” Herz said. “Yet it continued to sell fossil fuels at levels it knew would make its own dire predictions come true, and to lie about the harms.”

The case has already faced years of legal challenges, with ExxonMobil and Suncor repeatedly attempting to move proceedings to federal court. In 2023, the U.S. Supreme Court declined to hear the companies’ appeal, allowing the case to remain in Colorado state court.

Key Arguments Before the Colorado Supreme Court

Tuesday’s arguments focused on a critical legal question: whether Colorado’s state courts have the authority to hear the case or if the matter should fall under federal jurisdiction. ExxonMobil’s attorney, Kannon Shanmugam, argued that regulating climate-warming pollution should be a federal matter, warning that allowing state-level lawsuits could undermine national climate policy.

“We think Congress would have to authorize the state to permit this,” Shanmugam said.

On the other side, attorney Marco Simons, representing the Colorado communities, countered that the companies must be held responsible for the damages caused within the state.

“No constitutional text or federal statute would allow a Texas or Delaware corporation the unlimited right to cause injury to communities within the state of Colorado without paying for their share of the damage,” Simons said.

The Colorado lawsuit is part of a larger wave of legal actions across the country seeking to hold fossil fuel companies accountable for climate damages. Similar cases have been filed in Rhode Island, Baltimore, Hawaii, and multiple California cities. 

A recent ruling in Hawaii may bolster Boulder’s case. In 2023, the Hawaii Supreme Court allowed a Honolulu lawsuit against major oil companies to proceed in state court. In January 2024, the U.S. Supreme Court declined to hear an appeal, keeping the case in Hawaii’s jurisdiction.

Justice Richard Gabriel, a member of the Colorado Supreme Court, expressed concerns about the case, telling attorneys on both sides that he fears the cumulative claims against the oil industry by local governments could effectively serve as a form of regulation. "It would be shutting down all of the oil companies,” he predicts. 

What Comes Next?

The Colorado Supreme Court is expected to issue a decision in the coming months. If it upholds the lower court’s ruling, the Boulder lawsuit could move toward trial, barring further appeals.

Meanwhile, officials from the City of Boulder say they are committed to holding ExxonMobil and Suncor accountable.

“Boulder is increasingly burdened by the impacts of an altered climate, and our community cannot keep bearing the costs alone while those responsible avoid paying their fair share,” City Manager Nuria Rivera-Vandermyde said in a statement.

With climate-related disasters increasing in frequency and cost, Boulder and other municipalities across the U.S. are hoping these lawsuits can establish a legal precedent for corporate responsibility in the climate crisis.