California loses 20 years of climate progress as EPA targets key rule

Sacramento, California – The U.S. Environmental Protection Agency (EPA) unveiled a sweeping proposal Tuesday that would gut federal greenhouse gas emissions standards for vehicles and revoke the agency’s long-standing authority to regulate carbon dioxide and methane as air pollutants. The move, part of a broader deregulatory agenda by the Trump administration, was met with swift condemnation from California officials and environmental advocates who warned of dire consequences for public health and climate stability.

Announced at a truck dealership in Indiana by EPA Administrator Lee Zeldin, the proposal aims to reverse the EPA’s 2009 “endangerment finding”—the scientific and legal determination that greenhouse gases pose a threat to human health and welfare and can be regulated under the Clean Air Act. The endangerment finding underpins nearly all federal efforts to curb emissions from vehicles, the country’s largest source of direct greenhouse gas pollution.

“If the EPA moves forward with this proposal, it will mark one of the most damaging actions in the agency’s history,” said Vickie Patton, general counsel at the Environmental Defense Fund. “It is the EPA’s legal responsibility to protect the public from harmful pollution. Walking away from that duty will cost lives.”

California Governor Gavin Newsom, speaking in his role as Co-Chair of the U.S. Climate Alliance alongside Wisconsin Governor Tony Evers, denounced the move as “a reckless abandonment of science and the law.” In a joint statement, the governors emphasized that “Americans deserve the truth from their federal government about the climate crisis” and vowed continued state-level resistance.

The proposed rollback also includes plans to eliminate all tailpipe regulations related to greenhouse gas emissions while maintaining requirements for other pollutants like particulate matter and fuel economy labeling. That means the federal government would no longer enforce rules aimed at reducing carbon emissions from passenger vehicles, potentially stalling or reversing progress toward a lower-emissions transportation sector.

California, which has long led the nation in setting ambitious vehicle emissions standards, is again in the crosshairs. The Trump administration has already succeeded in getting Congress to revoke California’s EPA waiver, which had allowed the state to impose stricter rules than the federal baseline. While California has filed lawsuits challenging the waiver’s revocation and other deregulatory actions, the legal battles remain unresolved.

The implications for automakers are complex. Although public comment is open through September 21 and a hearing is scheduled for August, the mere uncertainty surrounding future standards could disrupt planning cycles for companies developing electric and low-emission vehicles. Meanwhile, recent congressional action to eliminate penalties for failing to meet fuel economy targets may disincentivize cleaner vehicle production altogether.

“This is a victory for oil companies, not American families,” said Fred Krupp, president of the Environmental Defense Fund. “If there are no enforced limits on pollution, you get more of it—making life more expensive and even more dangerous.”

Environmental groups, states, and public health advocates are expected to flood the EPA with comments opposing the rule. But as the Trump administration doubles down on its efforts to dismantle federal climate policy, the battle over emissions standards appears far from over.