WASHINGTON — SEPTEMBER 2, 2026 The U.S. District Court for the District of Columbia today issued a preliminary injunction in a case challenging the Trump EPA’s attacks on state clean vehicle standards.

“This is a welcome court decision that helps protect vital safeguards that 40 million Californians have long relied on to cut pollution, protect health and save money,” said Andy Su, Senior Transportation Attorney at Environmental Defense Fund. “We stand firmly with California to protect life-saving and money-saving clean vehicle standards.”

California sued after the Trump EPA summarily “reclassified” four Clean Air Act waivers of preemption for state protections to reduce pollution from new cars, trucks and some small off road equipment. The agency then submitted the “reclassifications” to Congress to encourage the use of the Congressional Review Act to try to overturn them. EPA has sought to invalidate several longstanding California Clean Air safeguards using this unlawful mechanism, including one for protections against vehicle pollution that took effect in 2009.

Today’s court decision requires that EPA withdraw or correct its reclassifications of the four waiver orders, and other such reclassifications, from orders to rules. In her opinion, Judge Howell highlights that EPA makes no “effort to justify this reclassification as legally viable” and that “the reason for this silence” is because the “waivers are properly considered adjudicatory orders under the APA, and therefore under the CRA, for both procedural and substantive reasons.” (Opinion at 63).

BACKGROUND

For more than half a century, the Clean Air Act has guaranteed California’s right to set stronger clean vehicle standards to protect its residents from dangerous air pollution. The law requires that EPA grant a waiver of preemption for those more protective standards in most cases, and EPA has granted over a hundred of such waivers over the decades.

Last year, EPA Administrator Lee Zeldin unilaterally “reclassified” some of the already-granted waivers as “rules” and then claimed they were subject to the Congressional Review Act (CRA) – a law that only applies to federal rules, not adjudicatory orders like waivers. That action broke from decades of consistent EPA practice, under Presidents of both parties, recognizing that preemption waivers are orders, not rules. The Senate Parliamentarian, the Government Accountability Office (the nonpartisan legislative agency historically responsible for determining which agency actions are subject to Congressional review) and the independent Congressional Research Service all also determined that the CRA did not apply in these cases. Today’s opinion likewise recognizes California is likely to succeed on its claims that the waivers are orders, consistent with EPA’s extensive and longstanding practice.

There are several pending lawsuits that are related to the administration’s earlier attempts last year to use the CRA to try to overturn other California clean vehicle protections. EDF has filed amicus briefs in support of California in several of those cases.