A legal challenge from the Golden State was widely anticipated. A provision built into the Clean Air Act gives California the right to set its own fuel efficiency standards, and state officials vowed to defend that right ahead of EPA's announcement last month.
Pruitt telegraphed a challenge to California's special status in April, saying federalism "doesn't mean that one state can dictate standards for the rest of the country."
Gov. Jerry Brown, state Attorney General Xavier Becerra and the California Air Resources Board filed the suit on Tuesday in the U.S. Court of Appeals for the District of Columbia Circuit. The suit asks the court to set aside and hold unlawful the process the EPA began last month to revise the fuel efficiency standards.
The suit argues the agency and Pruitt acted arbitrarily and capriciously, did not follow regulations and violated the Clean Air Act in making a final determination that "the current standards are not appropriate and should be revised." That determination kicked off the official revision process.
"The evidence is irrefutable: today's clean car standards are achievable, science-based and a boon for hardworking American families. But the EPA and Administrator Scott Pruitt refuse to do their job and enforce these standards," Becerra said in a statement.
The EPA did not immediately return a request for comment.
In his final determination last month, Pruitt said the Obama administration cut short an evaluation period meant to assess whether the nation's automakers could realistically achieve the EPA's previously established standards. The Obama EPA determined the standards were achievable, but Pruitt concluded that determination was wrong.
The so-called corporate average fuel economy, or CAFE standards, were set to roughly double from 2010 levels to about 50 miles per gallon.
The jurisdictions taking part in the suit are California, Connecticut, Delaware, Illinois, Iowa, Maine, Maryland, Massachusetts, Minnesota, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, Virginia, Washington state and Washington, D.C.