Washington, DC, Nov. 17, 2025 – A new memo released today by the Sierra Club analyzes the legal risks polluters would be exposed to if Donald Trump and Administrator Lee Zeldin choose to rescind the Environmental Protection Agency’s landmark Endangerment Finding, as they proposed in late July.
The 2009 finding—based on the overwhelming scientific evidence that carbon dioxide, methane, and other greenhouse gases endanger our health, our communities, and our economy by driving global climate change—authorizes the EPA to regulate those emissions under the Clean Air Act from cars and trucks, power plants, aircraft, and other sources. Under a Supreme Court precedent, EPA’s authority means that companies responsible for significant greenhouse gases, like automobile manufacturers, electric power companies, and oil and gas producers, are currently immune from federal common-law lawsuits over their greenhouse gas emissions. But if Trump and Zeldin proceed with their plan to rescind the Endangerment Finding and strip EPA of its authority to control greenhouse gas emissions, those companies’ immunity would disappear, and parties injured by greenhouse emissions may have little option but to pursue federal litigation.
The memo released today is authored by Amanda Leiter, who previously served as both an Associate Deputy General Counsel at EPA and a professor of environmental and administrative law at American University’s Washington College of Law, and Andres Restrepo, Senior Attorney with Sierra Club’s Environmental Law Program.
“Any effort to weaken or withdraw the Endangerment Finding would have a dramatically negative impact on our nation’s efforts to combat climate change and protect our families and communities from the harmful effects of greenhouse gas pollution. But what many may not fully realize is that it would also expose a large part of industry to legal uncertainty and potentially leave them liable in federal court for their contributions to climate change,” said Restrepo. “Repealing EPA’s authority to regulate climate pollution under the Clean Air Act would be a disastrous decision for many reasons, and the Sierra Club would explore all possible avenues—including but not limited to litigation—to hold polluters accountable in the absence of federal action.”
In late September, it was reported by E&E News that Zeldin planned to move forward with rescinding the finding without proper consideration of the legally required regulatory impact analysis–just days after the public comment period closed. More than 500,000 comments were submitted by members of the public, including a 200-page joint legal comment authored by the Sierra Club alongside the Center for Biological Diversity, Clean Air Task Force, Earthjustice, Environmental Defense Fund, and the Natural Resources Defense Council. That comment can be found here.
About the Sierra Club
The Sierra Club is America’s largest and most influential grassroots environmental organization, with millions of members and supporters. In addition to protecting every person’s right to get outdoors and access the healing power of nature, the Sierra Club works to promote clean energy, safeguard the health of our communities, protect wildlife, and preserve our remaining wild places through grassroots activism, public education, lobbying, and legal action. For more information, visit www.sierraclub.org.