States are suing the EPA for relinquishing its role as a greenhouse gas emissions regulator

"The lawsuit specifically argues that the EPA's decision to rescind a 2009 study that determined greenhouse gases are dangerous to public health was illegal. The study, which is the source of what's called the "Endangerment Finding," was one of several justifications - along with things like the Clean Air Act - for the agency's ability to regulate emissions."

"Rescinding the finding nullified the EPA's evidence for things like emissions standards and a variety of other regulations that attempted to reduce the amount of greenhouse gases produced by the automotive, coal and oil industries. The Trump administration framed the rollback as a cost-saving measure, but it was also a major blow to the government's ability to fight climate change."

"Determining the changes caused by greenhouse gases posed a risk to public health gave the EPA the authority to regulate them under its existing mandate to address air pollution. An authority it could have again, depending on the result of this litigation."

In February 2026, the EPA rescinded a 2009 study that determined greenhouse gases pose dangers to public health, known as the "Endangerment Finding." This decision eliminated the EPA's legal basis for regulating emissions from automotive, coal, and oil industries. Twenty-four states, led by California, Massachusetts, Connecticut, and New York, filed a lawsuit arguing the rescission was illegal. The Trump administration characterized the rollback as cost-saving, but it significantly weakened climate change mitigation efforts. Greenhouse gases like carbon dioxide, methane, and nitrous oxide accumulate in the atmosphere, warming the planet and disrupting weather patterns. The lawsuit, filed in the US Court of Appeals for the District of Columbia, seeks to restore the EPA's regulatory authority, though Congress could alternatively pass new legislation to achieve the same outcome.

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