The Environmental Protection Agency has finalized a rule rescinding its 2009 finding that greenhouse gases from new motor vehicles endanger public health and welfare, a step the agency says eliminates its authority under the Clean Air Act to set greenhouse-gas standards for cars and trucks. The action—grounded in a new legal interpretation and the Supreme Court’s “major questions” doctrine—has drawn sharp criticism from Democrats and legal and scientific experts and is expected to face court challenges.
On February 12, 2026, the U.S. Environmental Protection Agency finalized a rule rescinding the Obama-era “Endangerment and Cause or Contribute Findings for Greenhouse Gases Under Section 202(a)”—a 2009 determination that emissions of carbon dioxide and other greenhouse gases from new motor vehicles and engines contribute to air pollution that may reasonably be anticipated to endanger public health and welfare.
In the final rule, EPA said the 2009 finding had been a prerequisite for regulating greenhouse-gas emissions from new motor vehicles and engines under Section 202(a) of the Clean Air Act. The agency concluded that, absent that finding, it lacks statutory authority under Section 202(a) to prescribe greenhouse-gas standards for new motor vehicles and engines.
EPA’s final action also repeals all subsequent greenhouse-gas emission standards in its regulations for light-, medium- and heavy-duty on-highway vehicles and engines. EPA described the move as a major deregulatory action and said it would affect manufacturers’ obligations to measure, control and report greenhouse-gas emissions, while leaving in place federal rules governing conventional air pollutants.
The rule, published in the Federal Register on February 18, 2026, says it is based on the agency’s revised reading of Clean Air Act Section 202(a)(1) and that this interpretation is corroborated by the Supreme Court’s major-questions doctrine. The final rule also states that greenhouse-gas standards for new motor vehicles and engines do not affect in any “material way” the public-health and welfare concerns identified in the 2009 findings.
EPA’s action is likely to be challenged in court. The endangerment finding has long been treated by the federal government as a cornerstone for regulating greenhouse gases under the Clean Air Act, and the Supreme Court’s 2007 decision in Massachusetts v. EPA held that greenhouse gases are “air pollutants” under the Act—prompting EPA’s earlier determination that it had a duty to assess whether those emissions endanger public health or welfare.
Democrats on the House Science Committee said the administration’s repeal ignores well-established science and warned it would have serious consequences for public health and the planet. Environmental groups and other critics have likewise argued the rule conflicts with the structure of federal climate law and the Supreme Court’s prior recognition of EPA’s authority over greenhouse gases.
President Donald Trump and EPA Administrator Lee Zeldin appeared together at a White House event on February 12, 2026 tied to the rescission. Zeldin has said the administration’s approach is intended to align EPA regulations with what it views as the best reading of the Clean Air Act.
The rule’s effective date is April 20, 2026, according to the Federal Register publication.
