WASHINGTON (AP) —Donald Trump’s administration on Tuesday proposed revoking a scientific finding that has long been the central basis for U.S. action to regulate greenhouse gas emissions and fight climate change.

The proposed Environmental Protection Agency rule would rescind a 2009 declaration that carbon dioxide and other greenhouse gases endanger public health and welfare, The Associated Press reports. The “endangerment finding” is the legal underpinning of a host of climate regulations under the U.S. Clean Air Act for motor vehicles, power plants, and other pollution sources that are heating the planet.

Repealing the finding “will be the largest deregulatory action in the history of America,” EPA Administrator Lee Zeldin said Tuesday.

“There are people who, in the name of climate change, are willing to bankrupt the country,” Zeldin baselessly claimed on the conservative “Ruthless” podcast. “They created this endangerment finding and then they are able to put all these regulations on vehicles, on airplanes, on stationary sources, to basically regulate out of existence, in many cases, a lot of segments of our economy. And it cost Americans a lot of money.”

The EPA proposal must go through a lengthy review process, including public comment, before it is finalized, likely next year. Environmental groups are likely to challenge the rule change in court.

Zeldin called for a rewrite of the endangerment finding in March as part of a series of environmental rollbacks announced at the same time in what he said was “the greatest day of deregulation in American history.” A total of 31 key environmental rules on topics from clean air to clean water and climate change would be rolled back or repealed under Zeldin’s plan.

Under the Obama and Biden administrations, his predecessors at EPA “twisted the law, ignored precedent, and warped science to achieve their preferred ends and stick American families with hundreds of billions of dollars in hidden taxes every single year,” Zeldin told an event in Indiana announcing the proposed rule change.

Tailpipe Emission Limits Also Targeted

The EPA also called for rescinding limits on tailpipe emissions that were designed to encourage automakers to build and sell more electric vehicles, a rule Trump incorrectly labels an EV “mandate.” The transportation sector is the largest source of greenhouse gas emissions in the United States.

Environmental groups said Zeldin’s action seeks to deny reality even as weather disasters exacerbated by climate change grow worse in the U.S. and around the world.

“As Americans reel from deadly floods and heat waves, the Trump administration is trying to argue that the emissions turbocharging these disasters are not a threat,” said Christy Goldfuss, executive director of the U.S. Natural Resources Defense Council. “It boggles the mind and endangers the nation’s safety and welfare.”

Under Zeldin and Trump, “the EPA wants to shirk its responsibility to protect us from climate pollution, but science and the law say otherwise,” she added. “If EPA finalizes this illegal and cynical approach, we will see them in court.”

Three former EPA leaders have also criticized Zeldin, saying his March announcement targeting the endangerment finding and other rules imperilled the lives of millions of Americans and abandoned the agency’s dual mission to protect the environment and human health.

“If there’s an endangerment finding to be found anywhere, it should be found on this administration because what they’re doing is so contrary to what the Environmental Protection Agency is about,” Christine Todd Whitman, who led EPA under Republican President George W. Bush, said after Zeldin’s plan was made public.

The EPA proposal follows an executive order from Trump that directed the agency to submit a report “on the legality and continuing applicability” of the endangerment finding. Conservatives and some congressional Republicans hailed the plan, calling it a way to undo economically damaging rules to regulate greenhouse gases.

But environmental groups, legal experts, and Democrats said any attempt to repeal or roll back the endangerment finding would be an uphill task with slim chance of success. The Supreme Court ruled in 2007 that EPA has authority to regulate greenhouse gases as air pollutants under the Clean Air Act.

Passing Court Muster Could Be An Issue

The EPA proposal “seeks to deny settled science by creating legal distinctions that have no basis in the law,” said Abigail Dillen, president of the environmental law firm Earthjustice. Rather than take seriously its responsibility to protect public health, “the Trump administration is pretending that the pollution causing climate change is not hurting us, even as we suffer more devastating climate disasters every year,” she said.

If finalized, repeal of the endangerment finding would erase current limits on greenhouse gas pollution from cars, factories, power plants, and other sources and could prevent future administrations from proposing rules to tackle climate change.

“The endangerment finding is built on a rock-solid scientific foundation that has gotten even stronger over time,” said Fred Krupp, president of the U.S. Environmental Defense Fund. The finding “has supported commonsense solutions that reduce pollution, give us cleaner air, and protect our health and our jobs,” he said.

Climate scientists warned that overturning the endangerment finding would undermine decades of scientific progress and damage the credibility of U.S. institutions responsible for protecting the environment. The 12 hottest years on record have all occurred since 2009, and heat-related deaths are rising while wildfires are now more frequent and severe, said Scott Saleska, professor of ecology and evolutionary biology at the University of Arizona.

“To repeal the endangerment finding now would be like a driver who is speeding towards a cliff taking his foot off the brake and instead pressing the accelerator,” Saleska said.

Jim Walsh, policy director of the environmental group Food & Water Watch, used a more explosive metaphor. “Lee Zeldin’s assertion that the EPA shouldn’t address greenhouse gas emissions is like a fire chief claiming they shouldn’t fight fires,” he said. “It is as malicious as it is absurd.”

The Canadian Press republished this Associated Press story on July 29, 2025.