California’s Emissions Clash Escalates: DOJ Joins Fight Over Clean Truck Deal

California’s emissions policy is back in the national spotlight. The Department of Justice has stepped into court, challenging the Clean Truck Partnership (CTP) — a 2023 deal between the California Air Resources Board (CARB) and truck makers (OEMs).

The CTP let California delay some new truck emission rules, while manufacturers agreed not to sue. It centered on two rules:

• ACT: boost zero-emission truck sales.

• Omnibus NOx: slash diesel NOx emissions.

Both were later struck down by Congress and the President under the Congressional Review Act (CRA). That left manufacturers stuck: follow California’s rules and risk breaking federal law, or refuse and face California penalties. They sued CARB to void the deal.

Now Washington has intervened. The Justice Department says the CTP is illegal since CRA overturned the waivers California relied on. At the same time, a House committee is pressing CARB to explain if it is still enforcing rules that no longer stand.

The fight is no longer just state vs. industry — it’s California vs. federal government vs. Congress. The outcome will shape compliance costs and the future of U.S. truck emission standards.