California filed suit Friday against the federal government in a legal clash over state authority and environmental regulation, challenging what officials described as an unprecedented attempt by Congress to block California’s stringent vehicle emissions standards.
The lawsuit, led by California Attorney General Rob Bonta and joined by Governor Gavin Newsom and the California Air Resources Board, contests the use of the Congressional Review Act to nullify waivers previously granted by the Environmental Protection Agency. These waivers, long considered foundational to California’s environmental leadership, allow the state to set stricter vehicle emissions rules than federal standards.
Filed in the U.S. Court of Appeals, the lawsuit was joined by 10 other states, including New York, Massachusetts, and Washington, forming a broad coalition in defense of California’s Advanced Clean Cars II, Omnibus, and Advanced Clean Trucks programs.
“This is about California’s right to protect the health of its residents,” said Mr. Bonta in a statement. “The federal government’s effort to revoke these waivers is not only unlawful, it is reckless—placing both our clean air goals and green economy at risk.”
At the heart of the legal dispute is a series of EPA waivers issued since 2023, which enabled California to implement more aggressive standards for passenger cars and heavy-duty trucks, mandating increasing sales of zero-emission vehicles and tightening pollution thresholds for internal combustion engines. These rules are central to California’s efforts to combat air pollution and climate change. State officials argue that if the regulations are invalidated, California could lose an estimated $45 billion in avoidable health care costs over time.
The lawsuit accuses the Trump-era EPA of overstepping legal norms by transmitting the waivers to Congress as if they were federal rules, thereby inviting disapproval votes under the Congressional Review Act—a 1996 law intended to allow Congress to overturn federal regulations. But historically, the CRA has not been used to reverse agency waivers, which are considered adjudicatory decisions rather than rulemaking. Both the nonpartisan Government Accountability Office and the Senate Parliamentarian have previously concluded that the CRA does not apply to EPA waivers of this kind.
“This is a violation of long-standing precedent and a direct assault on our authority to lead on clean air,” said Mr. Newsom. “It’s a move straight out of the polluters’ playbook, and we will not let it stand.”
The EPA, under Republican and Democratic administrations alike, has granted California more than 75 waivers since the 1970s, recognizing the state’s unique air quality challenges and longstanding emissions control programs, which predate federal clean air legislation.
Environmental groups and public health advocates have raised alarms over the potential rollback. California remains home to several of the most polluted air basins in the country, and transportation remains the leading source of greenhouse gas emissions nationwide. In California, more than 2 million zero-emission vehicles have already been sold, and state officials say the clean vehicle market is accelerating faster than expected.
The regulations at stake include the Advanced Clean Cars II rule, which requires that by 2035, 80 percent of new passenger vehicles sold in the state must be fully electric, with the remainder allowed to be plug-in hybrids. The Advanced Clean Trucks rule mandates the sale of electric medium- and heavy-duty trucks, while the Omnibus rule imposes stricter limits on nitrogen oxide emissions from diesel engines.
The lawsuit argues that the disapproval resolutions passed by Congress are not only procedurally flawed but also violate the Constitution’s principles of federalism and separation of powers. It asks the court to invalidate the resolutions and order the federal government to honor the waivers as granted.
A spokesperson for the EPA declined to comment on pending litigation.
In the broader context of U.S. climate policy, the legal battle underscores the growing tension between federal and state authority over environmental regulation. With the Biden administration walking a fine line between its own climate ambitions and a divided Congress, California’s challenge sets up another high-stakes confrontation over who decides how clean American cars should be.