22 States Sue Trump EPA Over Rollback of Landmark 2009 Climate Rule

A coalition of 22 states, the District of Columbia, and New York City has taken legal action against the Trump administration. The lawsuit challenges the Environmental Protection Agency's (EPA) decision to revoke a key climate regulation from 2009.

California Governor Gavin Newsom condemned the move as 'corruption' and pledged to contest it in court.

The legal challenge was filed on March 19 in the U.S. Court of Appeals for the District of Columbia. It targets the EPA's February 12, 2026, decision to rescind the 2009 endangerment finding on greenhouse gases. That finding had classified CO₂ and other emissions as threats to public health, providing a legal foundation for climate rules under the Clean Air Act.

The revocation removes this basis, leaving existing climate regulations vulnerable to reversal. No replacement measures or new legal steps have been announced by the EPA. Instead, the decision effectively dismantles the framework for federal climate action.

Governor Newsom's sharp criticism framed the EPA's action as politically driven. His vow to fight it signals a prolonged legal battle over the future of U.S. climate policy.

The lawsuit now rests with the D.C. Circuit Court. A ruling could determine whether the EPA's revocation stands or if the 2009 endangerment finding is reinstated. The outcome will shape the legal groundwork for future climate regulations across the country.