Trump Administration to Rescind EPA Endangerment Finding Thursday, Dismantling the Legal Foundation for All U.S. Climate Regulation

The endangerment finding traces its origins to a landmark 2007 Supreme Court decision, Massachusetts v. EPA, in which the court ruled that the EPA was required to regulate carbon dioxide and other greenhouse gas emissions under the Clean Air Act if the agency determined they endangered public health. Two years later, in 2009, the EPA under President Obama issued that determination, concluding that the accumulation of six greenhouse gases in the atmosphere threatened both current and future generations.

Since then, the finding has served as the legal bedrock for a sweeping architecture of climate rules. It enabled the EPA to set emissions standards for cars and trucks, regulate carbon dioxide from coal and gas-fired power plants, require fossil fuel companies to report their emissions, and limit methane releases from oil and gas operations. Without it, the EPA says it will "lack statutory authority under Section 202(a) of the Clean Air Act" to prescribe standards for motor vehicle emissions — effectively deregulating the nation's largest direct source of greenhouse gas pollution: the transportation sector.

The finding has been upheld in court repeatedly, and the Supreme Court declined to hear an appeal challenging it as recently as 2023. Its proposed rescission was first announced by Zeldin in March 2025, when he declared the EPA would be "driving a dagger straight into the heart of the climate change religion." The agency submitted the proposed final rule to the Office of Management and Budget over the weekend, setting the stage for Thursday's formal announcement.

The EPA under Zeldin has taken what NPR describes as "more of a legal approach" to overturning the finding, rather than a purely scientific one. The agency argues that the original 2009 determination "unreasonably analyzed the scientific record" and that its projections were too pessimistic. In a draft rule released in August 2025, the EPA contended that the endangerment finding had overstated the risk of heat waves, projected more warming than has materialized, and discounted what it characterized as the benefits of increased atmospheric carbon dioxide, such as enhanced plant growth.

Much of the agency's scientific justification relied on a report commissioned by Energy Secretary Chris Wright through a controversial Climate Working Group at the Department of Energy. That report described increased CO2 as having a "greening" benefit and argued there was no clear trend in the frequency of extreme weather events. However, the scientific community has overwhelmingly rejected these arguments. A group of 85 climate scientists submitted a point-by-point rebuttal, writing that the DOE report "exhibits pervasive problems with misrepresentation" and "does not meet standards of quality, utility, objectivity and integrity appropriate for use in supporting policy making."

The American Geophysical Union called the report's information "inaccurate and cherry-picked," while the National Academies of Sciences, Engineering and Medicine issued its own analysis concluding that the original endangerment finding was accurate and had stood the test of time. A federal judge also ruled that Wright and the DOE had violated public transparency laws in forming the working group that authored the report, and the panel has since been disbanded. It remains unclear whether the final version of the rule will rely on the same contested scientific arguments or modify its justifications in response to the extensive public comment period.

The most immediate practical effect of rescinding the endangerment finding will be the elimination of greenhouse gas emissions standards for cars and trucks. The Biden administration had set ambitious targets that projected electric vehicles would comprise up to 56% of new auto sales by 2032. The Trump administration is expected to entirely scrap those restrictions. Leavitt indicated that the deregulation would reduce the sticker price of new cars, SUVs, and trucks, with the White House's $1.3 trillion savings figure largely derived from expected reductions in vehicle purchase costs.

However, the picture is more complex than the administration suggests. Electric vehicles typically cost more upfront in the U.S. but are generally cheaper to operate over their lifespan, and economic analyses found that under the more stringent Biden-era EPA rules, drivers would actually save money overall through reduced gasoline purchases. The move also comes as part of a broader rollback: Congress has eliminated consumer tax credits for EVs, California's longstanding authority to set its own vehicle emissions rules has been blocked, and federal fuel economy standards have been weakened. Congressional elimination of noncompliance penalties has effectively given automakers free rein to focus on large, less-efficient gas and diesel trucks.

Remarkably, even Tesla — an electric vehicle company led by one of the president's closest allies, Elon Musk — urged the administration in a September 2025 letter to preserve the endangerment finding, writing that it had "provided a stable regulatory platform for Tesla's extensive investments in product development and production" and that reversing it would "deprive consumers of choice and extensive economic benefits." MEMA, the trade group representing parts manufacturers who supply automakers, similarly asked the EPA to keep greenhouse gas rules in place, arguing they provide the stability American companies need to remain competitive against increasingly impressive and affordable Chinese EVs. Beyond vehicles, EPA Administrator Zeldin has proposed repealing carbon dioxide standards for power plants and has signaled that methane regulations for the oil and gas industry will also be reconsidered.

Environmental organizations have made clear they will fight the rescission in court immediately. Abigail Dillen, president of Earthjustice, called the move "a slap in the face to the millions of Americans who are living through climate disasters and their aftermath," vowing to "see this administration in court to ensure that our government does its job to protect us." The Natural Resources Defense Council has promised to fight the EPA "every step of the way," with attorney David Doniger arguing it will be "impossible" for the agency to defend the rule change given a "Denali-size mountain of evidence" that greenhouse gas pollution fuels climate change.

The legal battle will likely hinge on whether the EPA can credibly argue that the science has changed since 2009 — a challenging proposition given that the intervening years have only strengthened the scientific consensus. Copernicus, the EU's climate monitoring service, reports that the past 11 years have been the 11 warmest on record. The case is widely expected to reach the Supreme Court, where the outcome is uncertain. The court's 2022 decision in West Virginia v. EPA already narrowed the agency's authority to broadly regulate greenhouse gases from power plants, and the current court's composition may be more sympathetic to the administration's position than previous benches.

On Capitol Hill, the reaction has split along predictable partisan lines. Senate Minority Leader Chuck Schumer called the move "a corrupt giveaway to Big Oil, plain and simple," warning that "the blast radius of this reckless decision will span from San Diego to Portland, Maine and from Seattle to Miami." Meanwhile, the Heartland Institute, a conservative think tank, applauded the change, with President James Taylor calling the original endangerment finding "scientifically flawed and blatant political pandering." Some industry players have also expressed concern that eliminating the federal framework, rather than simply weakening it, could trigger a patchwork of state-by-state regulations that would be even harder to navigate.

The rescission of the endangerment finding places the United States further outside the international mainstream on climate policy at a time when the rest of the world is grappling with accelerating warming. According to data from Copernicus and the UK's Met Office, the global average temperature in 2025 was more than 1.4°C above pre-industrial levels — approaching the 1.5°C threshold that nearly 200 countries agreed to try to limit warming to under the 2015 Paris Agreement. Scientists warn that threshold will likely be breached by the end of this decade.

Dr. Samantha Burgess, deputy director of Copernicus, noted that even with the cooling influence of the La Niña weather pattern, 2025 was significantly warmer than temperatures just a decade ago. "If we go twenty years into the future and we look back at this period of the mid-2020s, we will see these years as relatively cool," she said. The persistence of extreme heat has surprised some scientists, with Dr. Zeke Hausfather of Berkeley Earth noting the data "suggests that there might be some mysteries that we haven't fully solved" beyond the expected warming trajectory.

France's President Emmanuel Macron has recently urged Europe to "start acting like a world power" on issues including climate, and the European Union continues to pursue aggressive emissions reduction targets. China, despite remaining the world's largest emitter, has been rapidly expanding its renewable energy capacity. The U.S. decision to dismantle its own regulatory framework could further erode American credibility in international climate negotiations and cede leadership in the clean energy technologies that are increasingly driving global economic competition.