( August 25, 2025, 3:16 PM EDT) -- SACRAMENTO, Calif. — In an intervenor complaint filed Aug. 22 in the U.S. District Court for the Eastern District of California, the United States and the U.S. Environmental Protection Agency echo the sentiments of a group of heavy-duty vehicle and engine developers in accusing the California Air Resources Board (CARB) of “defying the supremacy of federal authority” through its continued enforcement of restrictive statewide heavy-duty vehicle emissions standards following a congressional preemption pursuant to the Clean Air Act (CAA)....