The Trump administration’s stated purpose for the Safer Affordable Fuel Efficient (SAFE) Vehicles rule is to “give the American people greater access to safer, more affordable vehicles that are cleaner for the environment.” Proponents often point to a need for one national standard for fuel economy to provide regulatory certainty for the auto industry and benefit the economy.

However, Wimberger explained that accounting for the social cost of carbon reveals the true cost of rolling back federal fuel efficiency standards. The US government has not been “pricing pollution correctly,” Wimberger told subcommittee chairman Harley Rouda (D-Calif.). “There is a market failure that we haven’t really internalized the cost of not taking action,” she stated, pointing to the cost of increased asthma cases resulting from poorer air quality and the cost of climate damages.

“Those are facts that we have not accounted for in the overall pricing, so to completely ignore that would be to go back, and would be to completely erode any progress that we’ve seen both on the air quality front and on the mitigation of climate change,” Wimberger said.