WASHINGTON — The legal instrument the federal government uses to undo regulation moved again on Thursday, and it pointed at California. The Environmental Protection Agency transmitted four of the state’s air pollution waivers to Congress, the procedural step that puts each one on a 60-day clock the Senate has spent the past year using to nullify exactly this kind of rule.
The four rules are unglamorous on paper and consequential in fact, according to the EPA. They cover California’s Advanced Clean Cars I emissions standards, its reinstatement of that program, an amendment to its rules on small off-road engines like leaf blowers and lawn equipment, and a 2009 greenhouse gas standard for new vehicles. Together they make up most of what the state, the country’s largest car market, has used to drag the federal auto industry toward cleaner exhaust for the better part of two decades.
EPA Administrator Lee Zeldin framed the transmission as housekeeping. The agency, he said, is accountable to Congress and most importantly to the American people, and it is fulfilling its statutory obligation to submit these California waivers to Congress for review under the law. The legal theory he is leaning on is that previous administrations failed to send the same rules to Congress as the Congressional Review Act, the 1996 statute that lets a simple majority of both chambers void a recent regulation with the president’s signature, requires.
That theory is contested, and the track record explains why it matters. In early 2025 the EPA transmitted three California waivers using the same argument. By June, Congress had voted to disapprove all three, and President Trump signed the disapprovals into law, including the rule that would have phased out the sale of new gasoline-only cars in California by 2035. Toyota, General Motors and several other automakers had lobbied hard for the repeal. The waivers Thursday’s transmission opens up are the next layer down: not the headline 2035 phase-out, but the regulations underneath that have shaped American vehicle emissions since the Bush administration.
California’s response was sharp. Lauren Sanchez, who chairs the Air Resources Board, said the state will not stand idle while this federal administration continues its illegal and unconstitutional actions, a statement that carries a quiet legal claim: that whether the waivers are even subject to the Congressional Review Act in the first place remains genuinely unresolved. The Government Accountability Office concluded in 2023 that California waivers are not the kind of rule the CRA was designed to cover. The agency Zeldin runs disagrees, and so does the Republican leadership in both chambers.
The factual fight under the procedural one is over what California can still do. Under the Clean Air Act, the state has occupied a unique position since 1970, allowed to set vehicle emissions standards stricter than the federal floor because it had been regulating its own air pollution before the federal government got into the business. Other states can adopt California’s standards by reference, and seventeen of them do, which is why a regulation written in Sacramento ends up shaping the cars sold in Vermont and New Mexico. Strip California’s authority and the federal floor becomes the ceiling.
That is the prize the administration has been pursuing on multiple tracks at once. In February, the EPA moved to revoke the 2009 endangerment finding that underpins federal authority to regulate greenhouse gases from vehicles, the foundation that any waiver sits on, and 23 states sued, led by California and New York, arguing the move ignored the science the agency itself had certified. The lawsuit is pending in the DC Circuit. Thursday’s CRA transmissions advance the same project through a different door: even if the endangerment finding survives the courts, repealing the waivers in Congress would make the state’s authority to act on it largely theoretical.
The economic stakes have moved beyond environmental policy. American automakers have spent the better part of a decade building product roadmaps around California rules that are also European rules and increasingly Chinese ones, and the global EV market is not waiting on Washington. Toyota and GM lobbied for the 2025 repeals to relieve compliance pressure at home; the same companies face stricter standards in nearly every other market they sell into. The repeal does not eliminate the transition; it concentrates it in jurisdictions where American manufacturers have less voice.
The timing reads as policy choreography. This week an international team of scientists put human-caused warming at 1.37 degrees Celsius with the carbon budget for 1.5 degrees running out around 2030, and US transportation emissions are the single largest sectoral source of American greenhouse gases. The same administration that has spent the spring freezing wind permits at the Pentagon and opening roadless forests to logging is now dismantling vehicle emissions standards on a parallel track. The pieces do not have to be coordinated to add up.
What no one outside Congress can predict is the floor vote. The earlier waiver repeals passed on essentially party-line votes that Democrats argued, and the Senate parliamentarian initially questioned, were improper under CRA procedure. Republican leadership pushed through anyway, and the Supreme Court declined to intervene. The four new transmissions arrive into a chamber where the precedent is now set, which is part of what the EPA appears to be banking on: the legal argument no longer needs to win, because the political argument already has.
California’s Air Resources Board is not pretending the outcome is up for grabs. Sanchez’s statement was a vow to litigate, not to lobby, and that is consistent with the state’s pattern through this administration: lose the federal vote, sue, and try to keep the rule alive through injunctions while the political balance shifts. The bet is that the 2026 midterms and the 2028 election arrive faster than the courts can finish, and that the underlying technology, the EV models already in dealerships and the supplier base already retooled, makes a full retreat economically harder than the politics suggests.
The next 60 days will tell whether that bet survives the first round. The waivers are now on Capitol Hill, the votes are scheduled to be quick, and the president has already shown what he will sign. Whether the courts hold those signatures up, or whether California’s exception to federal vehicle regulation ends here, is the question this transmission was designed to force.
