California sues EPA to block move sending four Clean Air Act waivers to Congress

California sued the Environmental Protection Agency in federal court Monday, seeking to block the agency’s move to send four long-standing California Clean Air Act waiver decisions to Congress as if they were reviewable federal “rules” under the Congressional Review Act.

The case escalates a growing fight over California’s authority to enforce vehicle and engine emissions standards that are stricter than federal rules. At its core is a legal question with implications beyond the state: whether EPA can newly reclassify already granted Clean Air Act waivers as Congressional Review Act rules, opening them to possible congressional disapproval.

California Attorney General Rob Bonta, Gov. Gavin Newsom and the California Air Resources Board filed the complaint June 22 in the U.S. District Court for the District of Columbia. The case, a complaint for declaratory and injunctive relief, is listed as Case No. 26-2185. The defendants are the EPA and Administrator Lee Zeldin, sued in his official capacity.

California argues that EPA acted unlawfully when, on June 12, it transmitted four waiver actions to Congress after reclassifying them as rules. The complaint says that move violates the Administrative Procedure Act, exceeds EPA’s legal authority and breaks with decades of agency practice. The state is asking the court to declare EPA’s action unlawful, block it and restore the status quo that existed before the agency’s June 12 step.

The four waiver actions at issue span more than a decade. They are the 2009 waiver for California’s greenhouse gas standards for new motor vehicles; the 2013 waiver for Advanced Clean Cars I, known as ACC I; the 2022 reinstatement of parts of the ACC I waiver after actions taken during President Donald Trump’s first administration; and California’s Small Off-Road Engine, or SORE, rule amendments, which were authorized in late 2024 and noticed in early 2025.

EPA said June 12 that it had transmitted the four California waiver “rules” to Congress for review under the Congressional Review Act, a law that allows lawmakers to disapprove certain agency rules. In the agency’s press release, Zeldin said, “It is important for EPA to fulfill our statutory obligation to submit these California waivers to Congress for their review pursuant to the law.”

Under Section 209(b) of the Clean Air Act, California has a unique ability to seek EPA waivers letting it enforce vehicle emissions standards that are tougher than national requirements. Other states may adopt California’s standards under separate Clean Air Act provisions, which is one reason these waiver disputes carry national significance. California said EPA has granted the state more than 75 preemption waivers over time for updates to its emissions-control programs.

California’s lawsuit says EPA had never treated Clean Air Act waivers as Congressional Review Act rules in the more than 50 years since the Clean Air Act was enacted. That position aligns with a March 6, 2025, legal opinion from the U.S. Government Accountability Office, Congress’ audit and investigative arm, which concluded that waiver decisions are adjudicatory orders rather than CRA rules.

The new case also follows an earlier clash over three other California waiver decisions. EPA transmitted those actions to Congress on Feb. 14, 2025. Congress later passed Congressional Review Act disapproval resolutions, which were signed into law in mid-2025, and California challenged those actions in separate litigation.

Bonta, in a statement released with Monday’s filing, said, “The Trump Administration is doubling down on its unlawful attack on California’s longstanding authority to address air pollution and adopt clean vehicle and equipment standards that protect our State and residents.”

For now, the dispute is at its opening stage. The newly filed case in Washington asks the court to reverse EPA’s reclassification of the four waiver decisions and return matters to the position they were in before the agency sent them to Congress.