After the U.S. Environmental Protection Agency (EPA) revoked California’s waiver to set its own emissions standards under the Clean Air Act, several states, cities and environmental groups challenged both EPA’s revocation and the “One National Program Rule,” a rule issued jointly by EPA and the Department of Transportation’s (DOT) National Highway Traffic Safety Administration (NHTSA). In the Rule, NHTSA reasoned that the Energy Policy and Conservation Act of 1975 gives the federal government the statutory authority to set one set of national fuel economy standards and expressly preempts conflicting state programs. Accordingly, EPA withdrew the Clean Air Act waiver that the agency had granted to California in January 2013 to adopt more stringent fuel economy standards, which a number of other states have followed.
The three cases challenging the agencies’ actions, State of California et al v. Chao et al., Environmental Defense Fund v. Chao et al. and South Coast Air Quality Management District et al. v. Chao et al., were filed in the U.S. District Court for the District of Columbia. On December 3, 2019, DOT filed a motion arguing the cases should be dismissed or transferred to the U.S. Court of Appeals for the District of Columbia Circuit, and on December 6, the district court entered an order providing notice of its intent to consolidate the cases. Once the cases are consolidated, the court will need to address the question of its jurisdiction before any substantive challenges are considered.