On June 12, 2025, President Trump initiated the process of dismantling California’s vehicle emissions standards by signing three Congressional Review Act (CRA) resolutions. These resolutions revoked California’s waiver under the Clean Air Act, which had previously allowed the state to enforce stricter emissions standards than federal law.
The CRA repeals California’s CARB Advanced Clean Trucks and Heavy-Duty Engine emissions regulations. This decision was positively received by the trucking industry, which had advocated for relief from the financial and operational challenges posed by the deadlines for transitioning to zero-emission systems.
Impact of Emissions Regulation Changes
Three significant CARB regulations that are affected by the CRA include:
- Zero-Emission Vehicle (ZEV) Sales Mandate: Often referred to as California’s “gas-car ban,” this regulation mandated that by 2035, all new passenger vehicles sold in California must be electric or fuel-cell powered, with at least 80% being plug-in hybrids or ZEVs.
- Advanced Clean Trucks (ACT) Regulation: This rule required medium- and heavy-duty truck manufacturers to progressively increase their sales of zero-emission trucks from 2024 to 2035. Other states, including New York and New Jersey, also adopted this regulation.
- Low-NOx Omnibus “Heavy-Duty Engine” Rule: This regulation established more stringent nitrogen oxide (NOₓ) standards for new heavy-duty diesel engines, surpassing current federal levels set by the EPA. CARB-Adopting States also embraced this rule.
Litigation and Potential Consequences
Following Trump’s enactment of the CRAs, California, along with the CARB-Adopting States, filed a lawsuit. They contend that revoking waivers through the CRA is legally inappropriate, as waivers are not federal regulations subject to congressional override. The states argue that this rollback poses risks to public health, particularly in heavily polluted areas, and undermines state-level innovations in electric vehicle manufacturing and infrastructure.
In response, California Governor Gavin Newsom issued an executive order instructing the Air Resources Board to create replacement or enhanced emissions standards within sixty days and to publicly identify automakers and fleets adopting ZEV standards.
The actions taken by California and the CARB-Adopting States are significant given their substantial share of current and anticipated vehicle sales in the U.S. The standards set by CARB shape the trajectory of the automotive industry’s transition to electric vehicles. Thus, the litigation’s outcome could have a profound impact on the rate of adoption of EVs and other greenhouse gas emission-reduction technologies by original equipment manufacturers (OEMs) and commercial operators.
Next Steps for Motor Carriers & Private Fleets
The emissions mandates have created significant financial and logistical hurdles for fleet managers. The CARB regulations affect various operational aspects, including routing, vehicle deployment, and capital expenses. Despite the uncertainty surrounding ongoing litigation, industry stakeholders are relieved by the CRA’s enactment.
The litigation’s eventual outcome could reshape long-term competitive strategies and capital planning. If upheld, the CRA may exempt carriers operating across state lines from these emissions mandates, easing traditional business considerations. Conversely, if California prevails, a fragmented regulatory landscape could quickly reemerge. Hence, fleet management strategies should remain adaptable, with contingency planning seeming prudent for business leaders.
Furthermore, this rollback may prompt CARB and the CARB-Adopting States to devise new strategies to achieve their goals, potentially incentivizing EV adoption instead of banning internal combustion engines. Fleet operators must stay informed about evolving state laws and regulations, which could yield similar results to prior mandates or offer opportunities through new programs.
Finally, market forces will continue to influence sustainability strategies amongst large shippers and their boards. Even with reduced mandates, the pressure from investors and consumers for decarbonization remains strong. These elements may sustain a momentum toward transitioning away from internal combustion engines, with ongoing technological advancement and infrastructure growth furthering the financial viability and operational efficiency for motor carriers and private fleets.
