Ohio v. EPA

The Clean Air Act preempts state emissions standards for automobiles but allows EPA to issue a waiver allowing California to adopt its own standards (and other states to adopt California’s standards). California has long had EPA waivers for its emissions standards for various pollutants, and in 2012 EPA issued a new waiver for California’s standards for greenhouse gas emissions from automobiles and light trucks. During the Trump Administration, however, EPA withdrew the waiver, based in part on a rule issued by the National Highway Traffic Safety Administration (NHTSA) purporting to declare that California’s emissions standards were preempted by a federal statute that gives NHTSA authority to issue fuel economy standards for vehicles. After the Biden Administration took office, NHTSA rescinded its preemption rule and EPA rescinded the withdrawal of California’s Clean Air Act waiver. A group of states led by Ohio, as well as a number of right-wing organizations, filed petitions in the D.C. Circuit challenging the waiver.

Public Citizen, as part of a coalition of environmental and consumer NGOs supporting EPA’s restoration of the Clean Air Act waiver allowing California to issue greenhouse gas emission standards for motor vehicles, intervened to defend the Biden Administration’s restoration of the waiver and filed a short brief in support of the agency’s action. In a decision issued in April 2024, the D.C. Circuit held that the petitioners challenging the action lacked standing to bring some of their claims and that their claim that the EPA violated a constitutional requirement that the federal government treat states equally in terms of their sovereign authority lacked merit.