WASHINGTON — President Trump is strongly considering a plan to revoke California’s legal authority to set state tailpipe pollution standards that are stricter than federal regulations, according to three people familiar with the matter.
The potential challenge to California’s authority, which would be a stinging broadside to the state’s governor and environmentalists, has been widely anticipated. But what’s notable is that the administration would be decoupling its challenge to California from its broader plan to weaken federal fuel economy standards, the latest sign that its plans for that rollback have fallen into disarray.
Since the early months of the administration, the Environmental Protection Agency and the Transportation Department have been pursuing one of Mr. Trump’s most consequential attempts to weaken regulations designed to fight climate change: A sweeping rollback of Obama-era rules designed to cut the emissions of planet-warming greenhouse gases.
But that rollback has become bogged down, according to people who have worked on the project, largely because staff members have been unable so far to prepare adequate documents detailing the legal, technical, economic and scientific justifications for it.
The administration’s plans have been further complicated because major automakers have told the White House that they do not want such an aggressive rollback. In addition, four major automakers have signed a deal with California pledging to abide by the state’s stricter standards if the national rollback goes through.
“They are having a lot of problems,” said Margo Oge, a former E.P.A. official who now advises auto companies on vehicle emissions policy issues.
However, staff members months ago completed work on the simpler legal language required to revoke the California waiver.
“Unfortunately, California is trying to impose its failed policies on the rest of the country by making new cars significantly more expensive for American consumers and less safe,” said Russ Vought, the acting director of the White House Office of Management and Budget, in an emailed statement. “Even worse for Americans on the road, a handful of irresponsible automakers are aiding California’s radical agenda that will hurt every one of us.”
Mr. Trump’s supporters applauded the idea. “Withdrawing the California waiver is the most important part,” of the new fuel-economy rule, wrote Myron Ebell, who heads the energy program at the Competitive Enterprise Institute, an industry-funded research organization, and who led the administration’s transition at the E.P.A., in an email.
“It puts California back on an equal footing with the other 49 states and means that California cannot dictate what kinds of cars people can drive across the entire country,” he said. Revoking the waiver now, he said, also increases the likelihood that any legal challenges reach the Supreme Court before the end of Trump’s first term.
That is important because Trump administration lawyers would be expected to fight for the revocation of California’s waiver before the Supreme Court, but that would be unlikely if the case reached the court under a Democratic president.
California’s special right to set its own tailpipe pollution rules dates to the 1970 Clean Air Act, the landmark federal legislation designed to fight air pollution nationwide. The law granted California a waiver to set stricter rules of its own because the state already had clear air legislation in place.
A revocation of the California waiver would have national significance. Thirteen other states follow California’s tighter standards, together representing roughly a third of the national auto market. Because of that, the fight over federal auto emissions rules has the potential to split the United States auto market, with some states adhering to stricter pollution standards than others. For automakers, that represents a nightmare scenario.
The Obama-era tailpipe pollution rules that the administration hopes to weaken would require automakers to build vehicles that achieve an average fuel economy of 54.5 miles per gallon by 2025, cutting about six billion tons of carbon dioxide pollution over the lifetimes of those vehicles. The proposed Trump rule would lower the requirement to about 37 miles per gallon, allowing for most of that pollution to be emitted.
Originally, officials had hoped to complete work on that rule and introduce it by this spring, allowing time for the expected legal fight over the measure to reach the Supreme Court by 2020, during Mr. Trump’s first term.
As it became clearer in recent months that administration officials had not been able to complete the thousands of pages of analyses required to put forth the rollback of the broader rule on nationwide vehicle pollution, White House officials began considering moving forward with the one piece of the plan that was ready, according to people familiar with the matter, the revocation of the Clean Air Act provision giving California its special status.
Xavier Becerra, the California attorney general, restated his intention to sue over any attempt to undermine his state’s legal authority to set its own pollution standards. “California will continue its advance toward a cleaner future,” he wrote in an email.
A spokeswoman for the American Auto Alliance, which lobbies on behalf of the largest automakers, declined to comment until any plan had been made public.
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