The U.S. Supreme Court on Monday refused to review a challenge to the Environmental Protection Agency’s authority to allow California to set its own greenhouse gas emissions standards for vehicles, leaving intact a D.C. Circuit decision upholding the EPA’s waiver under the Clean Air Act.
The denial, issued in a brief order with no explanation, ends a push by red states to overturn California’s unique authority to impose stricter vehicle emissions rules. Justice Clarence Thomas indicated he would have granted the petition.
States’ Challenge to California’s “Special Status”
Ohio and 16 other states argued that the EPA’s practice of granting California waivers to establish independent emissions standards violated their constitutional right to “equal sovereignty.” In a July petition for writ of certiorari, Ohio said the Clean Air Act improperly “elevated California above all the other states” by granting it unique regulatory powers.
Congress included the waiver provision in the Clean Air Act decades ago, recognizing California’s leadership in regulating vehicle emissions. The EPA has issued such waivers consistently, including in 2022, enabling California to implement stricter greenhouse gas standards and zero-emission vehicle mandates.
