An electric pick-up truck is parked at the Rivian Automotive Inc facility in Costa Mesa, California, U.S.,November 1, 2023.
Last month, the U.S. Environmental Protection Agency under President Donald Trump sent the approval to Congress saying it was properly considered a rule under the Congressional Review Act. The GAO said the decision should be considered an order and is not reviewable.
As a candidate, Trump vowed to rescind waivers granted by the EPA under the Clean Air Act to California to require more EVs and tighter vehicle emissions standards. Those rules have been adopted by another 11 states, including New York, Massachusetts and Oregon.
The EPA, which last month submitted three waivers issued to California for review by Congress, said Thursday it believes those actions should properly be considered rules eligible for repeal by Congress.
California's rules require 35% of vehicles in the 2026 model year to be a zero-emission model- a figure automakers say is impossible to meet given current sales - rising to 68% by 2030. The state says the rule is crucial to meeting greenhouse gas emission reduction targets and cutting smog-forming pollutants.
Senate Environment and Public Works chair Shelley Moore Capito told Reuters that Republicans were considering next steps.
Senator Adam Schiff, a California Democrat, said the GAO ruling is "clearly consistent with prior decisions" that will be "enormously helpful in protecting California's ability to protect its citizens."
The EPA under former President Joe Biden took the position that the waiver was not a rule and therefore not reviewable by Congress.
California first announced a plan in 2020 to require that by 2035 at least 80% of new cars sold be electric and up to 20% plug-in hybrid models.
The EPA also granted in December a waiver for California's “Omnibus” low-NOx regulation for heavy-duty highway and off-road vehicles and engines, which it also submitted to Congress.
The U.S. Transportation Department is separately moving to undo aggressive fuel economy rules adopted by Biden.
