The claim: 

California’s tough car emission standards have long stuck in the craw of Republicans and car manufacturers. In the fall of 2019, Trump kicked that decades-long conflict into overdrive by rescinding the federal waiver that California needs to implement those beefier rules. 

“Federalism does not mean that one state can dictate standards for the nation,” said Environmental Protection Agency Secretary Andrew Wheeler in making the announcement.

Trump’s line: California’s regulations force manufacturers to produce cars that are more expensive and less safe. He has also argued that the state’s rules don’t even result in lower emissions because, by making new cars more expensive, they lead current drivers to hang on to their older, less fuel-efficient clunkers longer.

California disagrees and has sued over the new rule. Three times. 

The Trump Administration is revoking California’s Federal Waiver on emissions in order to produce far less expensive cars for the consumer, while at the same time making the cars substantially SAFER. This will lead to more production because of this pricing and safety……

— Donald J. Trump (@realDonaldTrump) September 18, 2019

The facts:

Even since the Clean Air Act was passed by Congress in 1970, California has gotten special permission to adopt its own, stronger rules as a way to combat the state’s infamous smog. Because California is such a massive market and because more than a dozen other states abide by the Sacramento standard, the policy has a discernible impact on national particulate and greenhouse gas emissions. It also drives the production decisions of auto manufacturers across the world.

Stuck between the two standards, Honda, Ford, Volkswagen and BMW cut a deal with California to voluntarily abide by a watered-down version of the state’s rules. General Motors, Fiat Chrysler, Toyota and Hyundai sided with the Trump administration, eliciting some pushback from the Newsom administration.

Whether the Trump administration has the right to revoke the state’s waiver is an unsettled legal question. History may be on California’s side: For half a century, the federal government has never unilaterally revoked a waiver. Ultimately, the Supreme Court may decide.

As to the president’s contention that California’s higher standards make cars both less safe and more expensive, prolonging the road-life of older, dirtier cars resulting in higher emissions, there doesn’t seem to be much evidence to back up either claim.

One analysis led by researchers at the University of Southern California, Yale and the National Bureau of Economic Research found the administration’s assessment was “at odds with basic economic theory and empirical studies.” That unfavorable view was shared by some within the Environmental Protection Agency itself. According to an internal agency presentation obtained by the Washington Post, agency officials warned that the administration’s vehicle emissions plan contained “a wide range of errors, use of outdated data, and unsupported assumptions.” 

Learn more about the tailpipe wars here.