Trump EPA set to repeal scientific finding that serves as basis for US climate change policy

The Trump administration announced Thursday it will revoke a key scientific finding that has been the foundation for U.S. climate regulation for over a decade, marking what environmental advocates call the most significant rollback of climate policy in American history.

The Environmental Protection Agency (EPA) plans to issue a final rule rescinding the 2009 “endangerment finding” – the Obama-era determination that carbon dioxide and other greenhouse gases pose a threat to public health and welfare. President Donald Trump and EPA Administrator Lee Zeldin will formalize the decision at a White House ceremony, according to White House press secretary Karoline Leavitt.

“This will be the largest deregulatory action in American history, and it will save the American people $1.3 trillion in crushing regulations,” Leavitt said. She added that the bulk of the savings would come from reduced costs for new vehicles, with EPA projections showing average per-vehicle savings exceeding $2,400 for popular light-duty cars, SUVs, and trucks.

The endangerment finding has served as the legal foundation for nearly all climate regulations implemented under the Clean Air Act since 2009, including emissions standards for vehicles, power plants, and other pollution sources. These regulations were designed to mitigate increasingly severe climate-related threats such as floods, heat waves, wildfires, and other natural disasters affecting the United States and global communities.

Legal challenges to the administration’s decision are inevitable. Environmental groups have already signaled their intent to fight the move in court, characterizing it as an unprecedented attack on federal climate action.

“The Trump administration is abandoning its core responsibility to keep us safe from extreme weather and accelerating climate change,” said Abigail Dillen, president of Earthjustice, a nonprofit environmental law firm. “There is no way to reconcile EPA’s decision with the law, the science and the reality of disasters that are hitting us harder every year. Earthjustice and our partners will see the Trump administration in court.”

EPA press secretary Brigit Hirsch defended the action, calling the Obama-era rule “one of the most damaging decisions in modern history” and noting that the agency “is actively working to deliver a historic action for the American people.”

Trump, who has previously dismissed climate change as a “hoax,” had earlier issued an executive order directing the EPA to review “the legality and continuing applicability” of the endangerment finding. This move fulfilled a long-standing goal of conservatives and some congressional Republicans who have sought to dismantle what they consider overly restrictive and economically harmful climate regulations.

Zeldin, a former Republican congressman appointed by Trump to lead the EPA last year, has been critical of Democratic predecessors, claiming they were “willing to bankrupt the country” in their climate change efforts.

“Democrats 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… segments of our economy,” Zeldin said when announcing the proposed rule in July. “And it cost Americans a lot of money.”

Environmental advocates strongly dispute these claims. Peter Zalzal, a lawyer and associate vice president of the Environmental Defense Fund, argued that the EPA’s action will lead to increased climate pollution, higher health insurance and fuel costs, and thousands of avoidable premature deaths.

“Zeldin’s push is cynical and deeply damaging, given the mountain of scientific evidence supporting the finding, the devastating climate harms Americans are experiencing right now and EPA’s clear obligation to protect Americans’ health and welfare,” Zalzal said.

Critics of the decision also point to the legal precedent established by the Supreme Court’s landmark 2007 ruling in Massachusetts v. EPA, which determined that greenhouse gases qualify as air pollutants under the Clean Air Act. Since that decision, courts have consistently rejected challenges to the endangerment finding, including a 2023 ruling by the U.S. Court of Appeals for the District of Columbia Circuit.

Following Zeldin’s proposal to repeal the rule, the National Academies of Sciences, Engineering, and Medicine reassessed the scientific basis for the 2009 finding. Their September report concluded that the original finding was “accurate, has stood the test of time, and is now reinforced by even stronger evidence.”

The panel of scientists emphasized that much of what was uncertain about climate science in 2009 has since been resolved. “The evidence for current and future harm to human health and welfare created by human-caused greenhouse gases is beyond scientific dispute,” they stated.