Correcting the Logic Behind the 2026 US Vehicle Emissions Standard Rollback
This journal article reviews the existing science on vehicle emission and fuel economy standards in the United States.
Abstract
Vehicle emission and fuel economy standards—the sector’s most important policies—have swung wildly in the US since 2000. Modest tightening of standards under the Bush administration was accelerated under Obama, partially rolled back under the first Trump administration, then reinstated and tightened under Biden. Yet the current Trump administration has gone further, with a complete elimination of the US Environmental Protection Agency (EPA) greenhouse gas (GHG) standards for vehicles. These regulatory swings each claim support from formal cost-benefit analysis, as required by executive orders. Yet the contradictory conclusions stem not from evolving evidence, but from selective assumptions and inconsistent interpretation of key evidence. We discuss how to interpret and apply the existing evidence correctly and demonstrate that correcting errors would overturn the justification for the elimination of the EPA GHG standards.
