Editorial Board

Back California Over Trump on Car Emissions

The state's authority to set high limits on greenhouse-gas emissions is fixed in U.S. law.

Helping America clear the air.

Photographer: Visions of America/UIG via Getty Images

Thanks to a peculiarity of U.S. law, California has special power to set car pollution standards that affect the whole country. And the whole country -- even the whole world -- has benefited as, over decades, the state has pushed automakers to create ever-better pollution-limiting technology and ever-more fuel-efficient cars. Today, in the face of President Donald Trump's threats to let greenhouse gases rip, California's help is needed more than ever.

The Trump administration has signaled a desire to undermine the state's de facto national authority. State leaders have vowed to resist, and are already moving ahead with stricter emissions standards. Fortunately, California has a good chance of winning this fight.

The state's prerogative stems from its historic efforts, dating from the 1960s, to restrict tailpipe emissions in order to reduce smog in Los Angeles. In 1970, when Congress passed the Clean Air Act, it recognized California's progress by authorizing it to receive waivers from the Environmental Protection Agency to continue enforcing its own regulations, as long as they remained at least as strict as the federal government's. Other states were allowed to follow California rules, and at this point more than a dozen do. Automakers have little choice but to see that all their cars comply.

By the early 2000s, the state had moved on from smog control to climate protection, setting high fuel-efficiency standards to limit carbon dioxide emissions. And although the EPA under George W. Bush resisted granting a waiver for these rules, once Barack Obama reached the White House, the state had its waiver, along with a deal to harmonize California's fuel-efficiency standards with new national ones -- the ones that the Trump administration now wants to set aside.

It's important to point out why the standards, though imperfect, are worth keeping. Tailpipe emissions are a leading source of greenhouse gases in the United States. And carbon dioxide emissions cannot be blocked with pollution-control devices; the best way to reduce them is to simply burn less fuel.

Granted, fuel standards aren't ideal. Automakers can work around them -- by selling bigger models, which aren't required to be as efficient as smaller ones. And cars that need less fuel encourage owners to drive them more, again undoing some of the environmental benefit. A better way to give both carmakers and car buyers an incentive to minimize fuel use would be to impose a carbon tax -- or at least a higher gasoline tax. But there's little political support for this smarter answer. Tough fuel-economy standards are better than the alternative, if the alternative is nothing.

Automakers say raising fuel efficiency costs too much, especially the scheduled boost to more than 54 miles per gallon by 2025. Trump and EPA Administrator Scott Pruitt, neither of whom are bothered by the threat of climate change, agree. As a matter of law, though, the administration cannot dial back fuel standards without justifying the change in the light of a Supreme Court decision that recognizes greenhouse gases as air pollutants in need of regulation.

Assuming the administration could overcome that hurdle, it would then need to justify withdrawing California's waiver for the 54-mpg standard. And there's no precedent for the EPA withdrawing such a waiver.

At best, from the administration's point of view, this is a fight that could be embroiled in lawsuits for years -- ensuring a long period of uncertainty for automakers and climate-conscious citizens alike. Unless he's willing to fight for a smarter policy, Trump should do the country a favor and leave the existing rules alone.

    --Editors: Mary Duenwald, Clive Crook.

    To contact the senior editor responsible for Bloomberg View’s editorials: David Shipley at davidshipley@bloomberg.net .

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