According to the United States Environmental Protection Agency’s (EPA), about 28 percent of our national gas emissions come from transportation sources - more than half of that is attributable to cars and other light-duty vehicles.
We recently blogged about how the new administration in Washington is attempting to scrap an EPA regulation that effectively mandates that roughly two-thirds of all vehicles sold in the United States be electric by model year 2032.
And that’s unfortunate because the amount of air pollution reduction such a regulation seems likely to bring about would be remarkable.
But that’s not all: This month we’ve also witnessed another course change by EPA regarding vehicle emission standards. On Feb. 14, EPA announced that it is sending the Biden Administration’s issuance of a waiver for California’s light-duty vehicle emission standards to Congress for review under the Congressional Review Act.
This set of California emission standards is referred to as the Advanced Clean Cars II rules and they do two noteworthy things:
They would ban the sale of new cars powered with internal combustion engines in California by 2035.
They would impose limits on the tailpipe emissions of new cars sold in California from model year 2026 through model year 2035.
The Clean Air Act generally prohibits the states from imposing their own rules regarding limitations on emissions from new motor vehicles – the Act contemplates that such limitations generally may be imposed only by EPA.
We say generally, however, because the Act includes a carve-out for California’s vehicle emission standards – EPA can waive the Act’s prohibition of state vehicle emission standards for those issued by California (although none of the other states).
Further, the Act allows other states to adopt California’s standards after EPA issued a waiver for them.
Indeed, back in 2006, the Pennsylvania Department of Environmental Protection (DEP) promulgated a regulation called the Clean Vehicles Program that requires new cars sold in Pennsylvania to adhere to vehicle emission limits set by California (but not California’s fleet efficiency standards, though).
“That means that California’s rules determine how much pollution can come out of a new car’s tailpipe in Pennsylvania, but do not determine what percentage - if any - of new cars in Pennsylvania must be electric,” GASP senior attorney John Baillie explained.
California submitted a request for a waiver of Clean Air Act preemption for the Advanced Clean Cars II rules to EPA in 2023. EPA approved that waiver request on December 17, 2024, and published notice of its approval in the Federal Register on January 6, 2025.
However, as we noted above, on Feb. 14, EPA sent the approved waiver to Congress for review under the Congressional Review Act.
What does this mean?
The Congressional Review Act, which has been on the books since the 1990s, requires federal agencies to submit new major federal regulations to Congress for its review, and gives Congress the power to disapprove any such regulation for up to 60 days after the regulation becomes effective.
Congressional disapproval is by a simple majority of both the House of Representatives and the Senate. Important to note: Once a regulation has been disapproved under the Congressional Review Act, it may not be reissued in substantially the same form.
EPA’s approval of California’s waiver request was published on Jan. 6 and became effective on that date. Accordingly, Congress has until March 7 to disapprove the waiver under the Congressional Review Act.
If it does so, EPA may not grant a request for a substantially similar waiver in the future.
“Where this is going is anybody’s guess.” Baillie said. “Maybe Congress will fail to act by March 7, but if it does act the rules governing tailpipe emissions for cars in the upcoming model years in California and other large states could be out the window, replaced with