California, States Urge Trump EPA to Abandon Plan to Scrap Greenhouse Gas Rules

A coalition of Democratic-led states, spearheaded by California, is urging the Trump administration to abandon its plan to repeal the legal foundation for U.S. greenhouse gas regulations.

The proposal, announced by EPA Administrator Lee Zeldin, seeks to revoke the 2009 “endangerment finding,” which determined that greenhouse gas emissions pose a threat to human health.

If finalized, the move would eliminate the basis for regulating emissions from vehicles, power plants, and industrial facilities, potentially dismantling decades of climate policy.

California Attorney General Rob Bonta blasted the proposal as unlawful, saying it relies on “a draft, unvetted, scientifically unsound report” to override well-established science. Attorneys general from Massachusetts, Arizona, and Michigan echoed concerns, warning that repealing the finding would strip away vehicle emissions standards and ignore the mounting costs of climate change.

The EPA has defended its proposal, arguing that rolling back regulations will save money and ease industry burdens. But opponents contend it represents a dangerous retreat from climate action, leaving the U.S. ill-equipped to address global warming. Virtual hearings are underway this week to gather public input as states prepare for a likely legal showdown.

Repealing the 2009 endangerment finding would be one of the most consequential regulatory changes in US environmental history. The finding provides the statutory basis under the Clean Air Act for essentially all federal greenhouse-gas regulations - vehicle standards, power-plant rules, industrial-facility permits. Reversal would trigger extensive litigation and potentially require legislative action to restore any regulatory authority.

The multi-state legal-challenge coalition (California, Massachusetts, Arizona, Michigan) signals that state-level enforcement will attempt to preserve climate regulatory capability even where federal authority is stripped. This pattern of state-federal divergence, previously seen on vehicle standards and other issues, is likely to become the dominant frame for US climate regulation over the coming years.

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