At the end of May, Congress made a ruling that California is not allowed to set its own policies regarding vehicle emissions. This essentially overruled California’s emissions board, the California Air Resources Board, also known as CARB. However, Governor Gavin Newsom and other California officials are working to ensure CARB is able to remain active, as are the emissions standards previously set by CARB.

Governor Newsom announced plans to file a lawsuit against to block Congress’ action.

Newsom wants California to continue to move forward with their plans for emission standards and is ready to argue this matter in court. The standards were previously approved by the federal government and only recently under fire with the new legislation. Additionally, major truck industry original equipment manufacturers agreed to the standards. Eleven industry leaders signed the Clean Truck Partnership, also known as the CTP. This was an agreement between CARB and vehicle manufacturers that pledged they will meet California’s emission standards by their deadline. Amongst the industry signers were Cummins, Daimler Trucks North America, Hino, Isuzu, then-Navistar, Paccar, the Truck and Engine Manufacturers Association, and Volvo Group North America.

The agreement was signed back in 2023.

Based on the agreement and early implementation of the standards, California leaders are working to maintain their standards. However, Congress has equally shown that they are ready to fight it out over the standards formally taking effect. There have been Joint Resolutions that have each passed Congress and merely await the President’s signature. These are Resolutions 87 and 89. They each claim that California’s emission standards violate Chapter 9 of title 5 of United States Code.

With these Congressional actions, technically no change has been made to affect the CTP.

The CARB Principal Deputy Executive Officer, Courtney Prideaux, recently attended the Advanced Clean Transportation Expo held in California. While there, she shared that despite the Congressional actions, which at the time were still pending, heavy truck original equipment manufacturers were still tied to follow the regulations they agreed to in the CTP.

In the CTP agreement, they agreed to a timeline affecting largely 2027 and later models.

Additionally, the CTP included a section in which the OEM signers agreed to abide by the ACT, or Advanced Clean Trucks regulation, even if litigation overrules CARB. The ACT was a regulation put forth in 2021 that laid out restrictions on how emission releasing vehicles could be managed. The rulings done by Congress currently suggest that ACT is null and void. However, based on text interpretation, this is not the case. The ACT waivers are still in place; therefore, OEMs must abide by them, per the agreement.

In the coming months, further actions will be taken from both sides to either secure CARB’s place in emission reduction or Congress’ place in ending that.