California auto emissions decision may bring showdown with Trump

California’s clean-air agency voted Friday to push ahead with stricter emissions standards for cars and trucks, setting up a potential legal battle with the Trump administration over the state’s plan to reduce planet-warming gases.

The vote, by the California Air Resources Board, is the boldest indication of California’s plan to stand up to President Donald Trump’s agenda. Leading politicians in the state, from the governor down to many mayors, have promised to lead the resistance to Trump’s policies.

Trump says dialing back emissions rules will help stimulate auto manufacturing, backing industry over environmental concerns. He vowed last week to ease the regulations. Automakers are aggressively pursuing those changes after years of supporting stricter standards.

But California can write its own standards because of a long-standing waiver granted under the Clean Air Act, giving the state — the country’s biggest auto market — major sway over the auto industry. Twelve other states, including New York and Pennsylvania, as well as Washington, D.C., follow Cal-

ifornia’s standards.

“All of the evidence — call it science, call it economics — shows that if anything, these standards should be even more aggressive,” said board member Daniel Sperling, a transportation expert at the University of California, Davis.

Adopted in 2012 under the Obama administration, the standards would require automakers to nearly double the average fuel economy of new cars and trucks by 2025, to 54.5 mpg, forcing automakers to speed development of highly fuel-efficient vehicles, including hybrid and electric cars. Trump intends to lower that target.

Now, the question is how — or whether — the Trump administration will handle California’s dissent. The administration could choose to revoke California’s waiver, at which point experts expect the state would sue.

All major automakers previously voiced support for the more stringent standards.

Automakers now complain about the steep technical challenge posed by the stringent standards. They have estimated that only about 3.5 percent of new vehicles are able to reach it. They have estimated that their industry would have to spend a “staggering” $200 billion by 2025 to comply.