The Trump administration is on the brink of what could prove its most consequential legal battle with the state of California, with EPA chief Scott Pruitt expected this week to 

Last week saw confirmation of months of White House and EPA leaks that President Donald Trump would throw out a 2012 Obama administration edict that required average miles per gallon to nearly double to 54.5 for automakers’ fleets of new cars and trucks by 2025. Trump’s skepticism about climate change made him particularly open to the argument from General Motors, Ford and Chrysler that out-of-touch regulators under the previous president were trying to force them to sell vehicles that U.S. consumers didn’t want to buy.

But as The New York Times reported over the weekend, Trump and Pruitt went further than automakers wanted both by rolling back mileage standards more than expected and by signalling their readiness for a court fight over the deference that federal regulators have traditionally shown to the California Air Resources Board.

The Golden State’s problems with smog in the Los Angeles Basin – visible in the 1973 EPA photo shown above – led to the first state law in the U.S. targeting air pollution being adopted in 1947, among many other precedent-setting regulations. The air board continued California’s role as a pioneer in setting vehicle emission standards after it was launched in 1968 under then-Gov. Ronald Reagan. Its vehicle emission and safety rules often end up being copied by Congress and federal regulators and by nations around the world. The state’s present rules are followed by 12 other states, including New York and Pennsylvania – meaning the Golden State dictates what automakers must provide in about one-third of all new cars sold in the U.S. each year.

California’s special status may be only state carve-out in federal law

But with California’s pollution problems beginning to look more like the rest of the nation’s in recent decades, Republicans have increasingly chafed at the idea that CARB and not the EPA should have the dominant policy-making role on vehicle fuel and emissions standards.

An analysis in The Atlantic laid out how unusual the state’s status is:

“California is written into the Clean Air Act by name: At any time, it can ask the EPA administrator for a waiver to restrict tailpipe pollution more stringently than the federal government. If its proposed rules are ‘at least as protective of public health and welfare’ as the EPA’s, then the administrator must grant the waiver.

“This power is reserved alone for California, and it only covers pollution from cars. No other state can ask for a waiver. (In all of federal law, this might be the only time that a specific state is given special authority under such a major statute.)”

The administration of President George W. Bush became the first to challenge California’s special status when it rejected the state’s request to expand its definition of what substances in the atmosphere it could regulate to include non-polluting greenhouse gases. That prompted the filing of a lawsuit in January 2008 by then-Attorney General Jerry Brown that was backed by Gov. Arnold Schwarzenegger. But it became moot after Barack Obama succeeded Bush in the White House and the EPA resumed treating California’s proposals with deference.

Over the past 14 months, California Attorney General Xavier Becerra has filed 28 lawsuits against the Trump administration, according to a tally kept by the Washington Post. But even before Becerra began his litigation, Gov. Brown anticipated the upcoming CARB-EPA fight and emphasized its importance. In comments made in December 2016 – a month after Trump’s election – Brown framed the dispute as having consequences for the “survivability of our world” because of the threat posed by global warming.

At an American Geophysical Union conference in San Francisco, according to a Sacramento Bee account, the governor said, “We’ve got the scientists, we’ve got the lawyers and we’re ready to fight. We’re ready to defend. …. And, if Trump turns off the satellites, California will launch its own damn satellite. We’re going to collect that data.”

President Trump on Wednesday launched the

At a ceremony at a Detroit-area auto facility after meeting with auto executives, Trump declared his intention to pursue “fair” regulations that “protect and defend” jobs.

Before his remarks, Trump staffers gave background briefings to reporters on his plans to scrap mileage rules approved by President Obama’s EPA in his final weeks on the job. The new rules would require cars and small trucks to average 54.5 miles per gallon in 2025, up from the present 36 miles per gallon.

Automakers were unhappy with the Obama administration’s speedy decision-making – new rules weren’t required until 2018. They believe the rules will require them to sell vehicles Americans don’t want to buy in an era in which gasoline prices are low and relatively stable because of a heavy increase in domestic oil production. Warning that the new rules would put more than 1 million jobs at risk, automakers have been lobbying Trump since they were enacted.

Brown administration officials have already filed a challenge to Trump’s directive, according to the Los Angeles Times. “Any weakening or delay of the national standards will result in increased harms to our natural resources, our economy, and our people,” the brief asserted.

13 states use California’s tougher standards

But while the president rattled state officials with his actions, he didn’t go as far as some environmentalists feared.

Under the federal Clean Air Act of 1970, California was given the right to waive federal vehicle mileage rules in favor of stricter standards because of the state’s severe problems with smog and ozone pollution in Southern California. The waiver allows other states to follow California’s tougher standards. Thirteen do, and as a result about 40 percent of the nation’s residents who buy about 40 percent of vehicles do so under California’s stricter rules, irking automakers who don’t like to have to deal with what are essentially two national standards.

The Trump administration could have tried to end California’s waiver entirely or prevent other states from using the Golden State’s rules. Instead, Reuters reported the administration hopes to work with the state on a compromise.

But that is close to certain to be a nonstarter, given Brown’s and the California Legislature’s approval of a law requiring the state to have greenhouse-gas emissions 40 percent below 1990 levels by 2030. Achieving that goal appears close to impossible without sharply cutting emissions from the state’s transportation sector, which generates 36 percent of California’s carbon emissions, according to the most recent statistics.

Vehicle emissions rule a potent weapon for state regulators

Stanford environmental law professor Michael Wara said tough vehicle mileage standards have been the state’s strongest tool in combating greenhouse gas emissions.

“California is going to fight, to deploy every resource it has, to keep this stuff, because this is big,” Wara told the San Francisco Chronicle.

Wednesday’s developments were foreshadowed by the January confirmation hearing of Environmental Protection Agency chief Scott Pruitt, like Trump a climate change skeptic and longtime EPA critic. Under questioning by Sen. Kamala Harris, D-San Francisco, Pruitt refused to say whether the Trump administration supported allowing California to continue to waive federal air pollution rules in favor of tougher standards.

Given that California’s waiver is written into federal law, it is unclear whether the Trump administration could force the state to follow federal rules. In 2008, George W. Bush’s administration challenged new state rules, prompting a lawsuit from then-Attorney General Jerry Brown that was joined by 15 other states. But no court decision was forthcoming before Barack Obama succeeded Bush the following year. The Obama administration quickly dropped the challenge.