Trump administration sues California over zero-emission vehicle laws

The Donald Trump administration announced Thursday that the Departments of Transportation and Justice filed a lawsuit against the state of California, arguing that state rules on zero-emission vehicles and tailpipe greenhouse gas emissions are overridden by federal law. The lawsuit, filed in federal court in Sacramento, contends that California's requirement that all new vehicles sold in the state be zero-emission by 2035 improperly regulates fuel economy. According to the administration, this domain falls under the federal authority of the National Highway Traffic Safety Administration (NHTSA).

"The Justice Department … has filed suit to stop California from imposing an illegal electric vehicle mandate through what are effectively state-specific mileage requirements for car manufacturers," the announcement states in part. "Federal law prohibits individual states from adopting regulations related to fuel economy."

Biden granted California exemptions

The California Air Resources Board adopted its Advanced Clean Cars II regulations in 2022, which expand previous laws aimed at limiting vehicle emissions and seek to eliminate the sale of new gas-powered cars in the state by 2035. Normally, states are prohibited from adopting fuel economy regulations under the Energy Policy and Conservation Act of 1975, which reserves that authority to NHTSA. However, California received several waivers to implement and enforce its clean vehicle standards from the Environmental Protection Agency (EPA) during the administration of former Democratic President Joe Biden. Last year, Trump signed a law overturning ACC II, which his administration has called an "illegal electric vehicle mandate."

The lawsuit marks the latest effort by the Trump administration to reverse vehicle emissions policies adopted during the Biden administration, which in 2024 granted California a waiver under the Clean Air Act that allowed the state to continue to move forward on its zero-emission vehicle goals. In June of last year, Trump signed a congressional resolution aimed at blocking California's rule phasing out new gas-powered cars. California responded by suing the federal government, with the office of state Attorney General Rob Bonta calling the measure an "illegal resolution."

In response, Governor Gavin Newsom signed an executive order reaffirming the state's commitment to expand the use of zero-emission vehicles. Newsom's office called the latest lawsuit "meritless" and stated that "California will continue to compete globally to win the market for clean vehicles."