The will open its latest term Monday morning by hearing arguments over whether Boulder can sue two oil and gas companies for their roles in climate change in a case that is garnering national attention because the decision could affect the outcome of other climate cases pending in the United States.
Suncor Energy and ExxonMobil are asking the Supreme Court to block Boulder’s climate lawsuit from proceeding in a Colorado district court, arguing that such cases should be heard in federal courts. The justices will not consider the merits of Boulder’s claims that the two companies knew their emissions caused climate change and deceived the public about the harm.
While the arguments will involve complex, tedious questions over legal jurisdiction, the stakes are high for oil and gas companies and those who want to make them pay for the environmental and human health harms caused by climate change.
For weeks, various interests have held forums and sent a barrage of news releases to the media to sway the court of public opinion on whether oil and gas companies knew about the damage their emissions were causing. The politics surrounding climate change are in full view as liberals and conservatives take sides in how the case should go. And billions of dollars are on the line should the oil and gas companies ultimately lose at trial, and that brings industry warnings that consumers would pay the price in more expensive fuel to power their homes, businesses and automobiles.
On Monday, recused himself from the case because he owns stock in other oil and gas companies. that it was a prudent decision but not required.
City and county elected leaders from Boulder are traveling to Washington, D.C., for , and environmental activists are planning a rally at 9 a.m. Monday outside the Boulder County courthouse.
Adam Sopko, an associate professor at the University of Colorado School of Law, said the case involves a complicated legal question about jurisdiction and “highly consequential matters of law and policy.”
But he also said the Supreme Court is drawing attention by placing the Boulder v Suncor case first on its docket for the 2026-2027 term. Oral arguments begin at 8 a.m. Monday.
“In other words, they are bringing the spotlight on their dockets,” he said.
Still, the Supreme Court’s decision could determine the fate of 30 other climate liability cases pending in various courts around the United States. Sopko, who co-authored an amicus brief that argues the Supreme Court lacks jurisdiction, said it will depend on the nuances of the justices’ opinion. That is expected to come in early 2027.
Officials from the city of Boulder, Boulder County, Suncor Energy and ExxonMobil either declined comment or did not respond to The Denver Post’s interview requests for this story.
Boulder’s lawsuit against Suncor, which owns the only oil refinery in Colorado, and ExxonMobil, the nation’s largest oil and gas company, has bounced around state and federal courts since it was filed in 2018 in Boulder County District Court as the two companies have fought to keep it from going to trial.
“These big oil companies are really desperate to escape trial in these cases so they’re asking the Supreme Court to step in and save them from trial,” said Corey Riday-White, legal director for The Center for Climate Integrity. “Itap clear the fossil fuel industry doesn’t want the damning evidence of their climate lies to be presented at trial.”
The city and county of Boulder want to hold the two companies liable for damages caused by climate change, including devastating floods and wildfires, a diminishing water supply and poor air quality. Boulder wants the courts to force the companies to pay for the costs of climate impact. The lawsuit does not seek to stop fossil fuel production in Colorado or to regulate emissions.
Over the past eight years, thousands of pages of legal documents have been filed as the companies tried unsuccessfully to move the case to federal court. They also lost after filing a motion to dismiss in state court.
Most recently, the companies asked the Colorado Supreme Court to intervene and decide if the state courts have jurisdiction. But the state supreme court affirmed in a 5-2 decision that Boulder’s legal claims are not preempted by federal law and that a trial could proceed in Boulder district court.
Now the companies are asking the U.S. Supreme Court to intervene. They claim that federal law shields them from lawsuits over climate change and its associated harms and that state law cannot apply.
Some legal experts argue that Boulder should not be able to sue in state court because harmful greenhouse gas emissions originate in other states and overseas. Emissions that originate outside of Colorado should not be part of a lawsuit that is adjudicated in state courts, they argue.
That’s not how civil cases should work, said Phil Goldberg, a lawyer for the Manufacturers Accountability Project, which is funded by the National Association of Manufacturers.
“The rights and responsibility for climate change have to be decided at the federal level,” Goldberg said. “You can’t let one state decide climate law for the rest of the country or the rest of the world for that matter.”
Others warn that if Boulder’s lawsuit is successful oil and gas companies could be financially crippled and other industries will be the next in line for lawsuits over climate change.
“All you have to do is swap the energy defendants and the name Suncor and itap the same strategy,” said Michael Toth, research director at the at The University of Texas at Austin. “If it can happen to one industry, it can happen to all industries.”
Chris Winter, executive director of CU’s for Natural Resources, Energy and Environmental Law, said the climate case puts the federal government, particularly the Trump administration and the Environmental Protection Agency, in an awkward position.
In September, the EPA announced it will repeal rules that limit planet-warming greenhouse gas emissions from power plants that burn fossil fuels and will take a step to prevent future presidents from regulating pollution, saying the EPA lacks authority under the federal Clean Air Act to regulate greenhouse gas emissions.
In the Boulder climate case, however, the U.S. Department of Justice wrote a brief that argues federal law preempts state law in climate cases.
Winter described the administration’s conflicting positions as a “Kafkaesque disorientation.”
“How can we be hearing a statutory preemption argument from the oil industry and, by the way, from the Department of Justice, at the same time that we’re hearing the federal government say, ‘Oh, we have no statutory authority to regulate greenhouse gas emissions under the Clean Air Act?” Winter said Wednesday during a panel discussion on the case at CU’s law school. “So that’s awfully confusing.”
