Environmentalist groups and others sued the U.S. Environmental Protection Agency (EPA) on Feb. 18 over the agency’s recent decision to repeal a finding that served as the basis for federal climate regulations.
The American Public Health Association, American Lung Association, Environmental Defense Fund, Natural Resources Defense Council Inc., Union of Concerned Scientists, and other organizations filed their new lawsuit in the U.S. Court of Appeals for the District of Columbia Circuit. The federal Clean Air Act requires lawsuits challenging actions under the act to be initiated in the D.C. Circuit Court.
The groups are asking the court to review the EPA’s move to repeal a 2009 rule known as the endangerment finding that gave the federal government authority to regulate greenhouse gas emissions.
The brief petition does not present arguments for why the court should hear the case. The organizations are expected to justify their request in later court filings.
Peter Zalzal, associate vice president of clean air strategies at the Environmental Defense Fund, said repealing the finding is dangerous.
“People everywhere will face more pollution, higher costs, and thousands of avoidable deaths,” Zalzal said in a statement.
He said the EPA’s decision “tramples mountains of scientific evidence, ignores the law, and is fundamentally at odds with EPA’s core responsibility” to protect people from dangerous pollution.
The new legal action came after the EPA on Feb. 12 announced it was repealing the finding that held that carbon dioxide, hydrofluorocarbons, methane, nitrous oxide, perfluorocarbons, and sulfur hexafluoride posed a danger to public health. The repeal affects all greenhouse gas emissions standards for light-duty, medium-duty, and heavy-duty vehicles and engines.
President Donald Trump said at a White House event that “these crippling restrictions were a major factor in driving up car prices to unprecedented levels” and that they made the quality of cars worse.
“This determination had no basis in fact, none whatsoever, and it had no basis in law,” Trump said.
The EPA adopted the regulation following the 5–4 Supreme Court ruling in Massachusetts v. EPA (2007). The high court held that under the Clean Air Act, the agency was required to make a scientific determination about whether greenhouse gases constituted air pollution. The court said that if the agency determined they were pollutants, the federal law allowed the EPA to regulate them to protect public health.
The EPA issued the endangerment finding two years later, which allowed the federal government to regulate greenhouse gases.
The six kinds of gases encompassed by the rule repeal are gases that trap heat in the atmosphere, according to an EPA webpage last updated in December 2025.
The EPA published a notice in the Federal Register on Feb. 18 stating that the repeal will take effect on April 20.
The agency said it now takes the position that the repeal allows it to “effectuate the best reading” of Clean Air Act provisions.
In a reversal of EPA policy, the agency said in the notice that it now concludes that it lacks statutory authority to regulate greenhouse gas emissions “in response to global climate change concerns.”
Climate change policy should be made by Congress, and “Congress did not decide the Nation’s policy response” to climate change when it enacted the domestic air pollution provisions of the Clean Air Act almost 60 years ago, the notice states.
The EPA “continues to harbor concerns regarding the scientific analysis contained in the Endangerment Finding,” the notice states.
In response to a request for comment from The Epoch Times, an EPA spokesperson said, “The Trump EPA is committed to following the law exactly as it is written and as Congress intended—not as others might wish it to be.”
The spokesperson said that the endangerment finding is not valid and that the EPA cannot enforce regulations created under it.
“Congress never intended to give EPA authority to impose [greenhouse gas] regulations for cars and trucks,” the spokesperson added.
The new lawsuit may eventually end up before the Supreme Court, and the factors in challenges to federal agency actions have changed since the 2007 ruling in Massachusetts v. EPA.
In 2022, the Supreme Court held in West Virginia v. EPA that the Clean Air Act doesn’t give the EPA widespread power to regulate carbon dioxide emissions.
In 2024, the Supreme Court in Loper Bright Enterprises v. Raimondo overturned the Chevron deference doctrine, making it more difficult for unelected government officials to generate new regulations.
Travis Gillmore contributed to this report.
This article by Matthew Vadum appeared Feb. 18, 2026, in The Epoch Times.