Trump EPA repeals the 2009 endangerment finding, stripping federal authority to regulate greenhouse gases

On February 12, 2026, EPA Administrator Lee Zeldin stood with President Trump at the White House and announced what he called the single largest deregulatory action in U.S. history: the repeal of the 2009 greenhouse gas endangerment finding. That finding — a scientific determination that greenhouse gases threaten public health — was the legal cornerstone for every major federal climate regulation, from vehicle emission standards to power plant rules to limits on oil and gas methane. Without it, the EPA argues it has no legal authority under the Clean Air Act to regulate greenhouse gas emissions at all.

The 2009 endangerment finding itself was the product of a 2007 Supreme Court ruling — Massachusetts v. EPA — that found greenhouse gases are air pollutants covered by the Clean Air Act and ordered the EPA to assess whether they endanger public health. After President Obama took office, the EPA formally made that finding in December 2009. It wasn't a regulation itself, but it was the legal trigger for all subsequent climate rules. Repealing it unravels that entire regulatory structure.

Environmental and public health groups filed lawsuits within hours of the repeal being published in the Federal Register on February 12, 2026. The Conservation Law Foundation and more than a dozen other organizations argue that the repeal violates the Administrative Procedure Act and conflicts directly with the Supreme Court's 2007 ruling that greenhouse gases are air pollutants. Legal experts say this fight will likely reach the Supreme Court, but the EPA's rollback of climate rules is proceeding regardless.