The state of California filed a suit against the Environmental Protection Agency (EPA) on Monday over the federal government’s continued efforts to interfere with the state’s ability to enforce its own emission standards and anti-pollution regulations.

Last week, the EPA submitted four preemption waivers, granted to California under the Clean Air Act, to Congress for reclassification as “‘rules’ subject to congressional disapproval,” effectively subjecting them to the Congressional Review Act and opening the door for the federal government control of California’s environmental regulations. The present lawsuit is challenging the reclassificaiton of these waivers.

California asserts that the waivers constitute “finalized adjudicatory orders” rather than rules. According to the complaint, the federal government is attempting to misuse the Administrative Procedure Act (APA) by reclassifying the waivers as rules to enable the EPA to administratively revoke the waivers.

The waivers enabled California to enact its own Greenhouse Gas Emission Standards for cars in 2008, the Advance Clean Cars I (ACC I) rules in 2012, and amendments to the Small Offroad Engine rules. Essentially, the waivers permit California to adopt more stringent emission regulations than those of the EPA, should it see fit.

These waivers have been never been considered “rules” subject to Congressional disapproval in the past, although the Trump administration did rescind parts of ACC I, enacted by California utilizing the waivers. Vowing to “vigorously defend” California’s authority to implement and enforce its environmental laws, state Attorney General Rob Bonta 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 fifty years, both Democratic and Republican administrations have agreed that EPA Clean Air Act waivers are not rules, and EPA’s unlawful attempt to reclassify them — years after the fact — is an illegal attempt to take down these important tools. These latest illegal actions would mean more pollution, poorer air quality, more market uncertainty, and greater health risks for communities already overburdened by emissions. California will continue to fight against the Trump Administration’s lawless overreach and vigorously defend our authority to protect the health and well-being of our communities and the environment.

California Air Resources Board chair Lauren Sanchez further accused the federal government of creating chaos, getting “caught up in short-sighted political fights,” and putting the health of millions of Californians at risk. Sanchez said that Californians will not stand by idly, pledging that “we will defend our authority, protect public health, and continue working toward a cleaner, healthier future.”

The complaint notes that EPA tried this in 2025, resulting in Congressional resolutions disapproving three different targeted waivers. In that previous instance, California was joined in a similar suit against the federal government by Colorado, Delaware, Massachusetts, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont and Washington.

The present suit is a lone fight launched by California. Among other things, it asks the court to vacate the EPA’s reclassification and submission actions to Congress, and declare such actions a violation of the APA; declare that the four concerned waivers are not “rules” within the meaning of the APA; declare that EPA’s reclassification and submission actions as ultra vires; preliminarily enjoin the EPA to withdraw its reclassification and submission actions; and permanently enjoin EPA from repeating the reclassification and submission actions with respect to the concerned waivers and other previously granted waivers.

California and the federal government have been at loggerheads over such questions for quite sometime now. In March, the Justice Department (DOJ) filed a lawsuit against the California Air Resources Board (CARB) in an effort to block the state from enforcing carbon dioxide (CO2) and zero-emission vehicle (ZEV) mandates, on the grounds that federal law prohibits state regulation in this area. Last August, the DOJ filed suit against California seeking to prevent the state from enforcing its own emission standards for heavy trucks. In July 2022, in what was seen as a direct retort to the US Supreme Court’s refusal to block the Texas “heartbeat” anti-abortion bill that permits lawsuits against anyone who helps a woman seek access to abortion, California Governor Gavin Newsom signed a similar bill permitting private citizens to bring lawsuits against those who “make, sell, transport, or import” guns.