Trump fuel economy rollback is based on misleading and shoddy calculations, study finds

The Trump administration's plan to roll back vehicle fuel economy standards is based on a flawed and misleading analysis, a team of economists and other independent experts found.
(Al Seib / Los Angeles Times)

The Trump administration’s proposal to roll back fuel economy standards relies on an error-ridden and misleading analysis that overestimates the costs and understates the benefits of tighter regulation, an independent study by leading economists, engineers and other experts has found.

Findings published in the journal Science describe the Trump administration’s cost-benefit analysis as marred by mistakes and miscalculations, based on cherry-picked data and faulty assumptions and skewed in its conclusions. The analysis “has fundamental flaws and inconsistencies, is at odds with basic economic theory and empirical studies, [and] is misleading,” the researchers wrote.

The blunt assessment from a team of 11 experts at UC Berkeley, MIT, Carnegie Mellon, Yale and other universities casts more doubt on the underpinnings of President Trump’s plan to halt tough Obama-era rules requiring improvements in fuel economy. It lends support to California and other states fighting to hold onto the miles-per-gallon targets — the single biggest federal action to fight climate change.


The Environmental Protection Agency and the National Highway Traffic Safety Administration launched the rollback in August. While acknowledging it would increase oil consumption, air pollution and planet-warming emissions, they argued that tough fuel efficiency standards endanger drivers.

Stringent miles-per-gallon targets, they argued, would make new cars too expensive and force people to stay in older vehicles that lack the latest safety features. Officials also said the strict rules would push those who do upgrade into smaller, lighter and less safe cars. Abandoning Obama-era standards, they said, would prevent thousands of traffic injuries and fatalities, a conclusion that is contradicted by previous federal studies, EPA staff and is reportedly being reconsidered by the administration.

Researchers moved quickly to scrutinize the Trump administration’s rationale and found it overstated the benefits of unraveling the rules by at least $112 billion.

They came to the opposite conclusion: Weakening the rules would be more damaging than keeping them in place.

“We see no economic justification to keep the standard flat,” the study says.

Antonio M. Bento, a USC professor of public policy and economics and the study’s lead author, said, “It appears federal officials cherry-picked data to support a predetermined conclusion that the clean-car standards will lead to too many highway deaths.

“But this is wrong, and for various reasons,” Bento added. “And it was done in a very sloppy fashion, by inflating the costs and cutting the benefits in an almost embarrassing, dishonest way.”


The EPA did not respond to a request for comment on the findings. NHTSA said it could not comment on a study it has not yet read.

The agencies’ plan would replace aggressive miles-per-gallon standards with ones that are even more lax than what automakers had wanted, while seeking to revoke the authority of California and other like-minded states to adopt their own, stricter rules.

The tougher Obama-era standards aim to boost the fleetwide average fuel economy of cars and trucks to about 36 miles per gallon in real-world driving by 2025. The Trump administration proposal freezes fuel efficiency at the 2020 level of about 30 mpg.

One of the biggest errors independent researchers found in the federal government’s analysis was a mistaken conclusion that relaxing fuel economy rules will shrink the nation’s vehicle fleet by 6 million cars by 2029. That’s in violation of basic economic principles, which hold that loosening fuel economy regulations will make new cars less expensive and increase demand.

Researchers say the nation’s fleet wouldn’t shrink and would likely grow with eased standards, meaning federal authorities severely underestimated how a rollback would actually increase driving, gas consumption, air pollution and traffic fatalities.

Experts also faulted the administration’s analysis for accounting only for the domestic benefits of cutting carbon emissions while ignoring global ones. As a result of this unorthodox calculation, the proposal dramatically understates the overall economic benefit of reducing greenhouse gas emissions.


The experts’ findings give a boost to California and other like-minded states fighting the proposed rollback, which have made similar criticisms of the Trump administration’s analysis and say the plan cannot be justified on legal, economic, environmental or legal grounds.

“One of the world’s most respected independent scientific journals has just exposed the lack of foundation for the Trump administration’s proposal,” said Mary Nichols, who chairs the California Air Resources Board. “As we have said repeatedly, this proposal should be withdrawn.”

In hundreds of pages of comments, legal and technical analyses submitted in October, California officials cited the federal proposal’s “numerous flaws, use of faulty assumptions, incorrect modeling, cherry-picked data and fundamental misunderstanding of consumer behavior.”