On June 12, in accordance with the Congressional Review Act, the EPA transmitted the agency's Jan. 6, 2025, waiver authorization of California's Small Off-Road Engine amendments, to Congress for review. Additional waivers transmitted for Congressional review at that time were those for Advanced Clean Cars I, Reinstatement of ACC I, and the Green House Gas Emission Standards for light-duty vehicles. Congress may use its authority under the CRA to disapprove the waivers, nullifying EPA's authorization and CARB's ability to enforce these rules. The CRA requires all federal agencies to report rules to Congress before any agency action can take effect. Congress has 60 session days to act on a resolution to disapprove any federal agency rule once it has been submitted.
Last week Senator Lummis (WY) and Representative Obernolte (CA), with several co-sponsors, introduced resolutions of disapproval for the SORE waiver authorization. OPEI anticipates Congress may vote on the resolutions as early as September.
In February 2025, the EPA determined waivers are rules subject to review under the CRA and proceeded to transmit three waiver authorizations to Congress — California's Advanced Clean Cars II, Advanced Clean Trucks, and the Omnibus NOx rule. Congress approved resolutions of disapproval for all three waivers in June 2025, and President Trump subsequently signed the resolutions into law, effectively overturning EPA's prior waiver authorizations and nullifying California's latest and most stringent vehicle emissions standards for light-duty vehicles and trucks. Manufacturers that were required to comply with CARB's most recent rules may now certify vehicles to the CARB rules and limits that immediately preceded the nullified rules, or alternatively, submit to CARB for review the certificates of conformity received from EPA.
A CRA resolution of disapproval is final and cannot be legally challenged. Additionally, the CRA prohibits an agency from issuing a rule "substantially similar" to a disapproved rule unless explicitly authorized by subsequent legislation. To protect and defend its mobile source rulemaking authority, California has filed separate suits against EPA for the agency's 2025 and 2026 transmissions of waivers to Congress, arguing the agency erred in its determination that waivers are rules subject to the CRA. Under the previous administration, EPA determined that waivers were "adjudicatory orders" rather than rules subject to Congressional review under the CRA, an opinion supported by the Senate Parliamentarian and the U.S. Government Accountability Office.
California's legal actions against EPA continue to play out in the courts — the 2025 transmissions are being challenged in the District Court for the Northern District of California, and the 2026 transmissions are being challenged in the District Court for the District of Columbia. While litigation is pending, CARB has advised vehicle manufacturers that if the courts determine that the resolutions of disapproval are unconstitutional, the agency may retroactively enforce against certifications for less stringent standards for the model years that would have otherwise been covered by the nullified rules (e.g. 2025, 2026...). It is unclear at this time what certification and/or potential retroactive enforcement policy CARB will pursue if the SORE waiver is disapproved.
OPEI has a long history of collaboration with CARB and EPA to develop impactful emissions regulations. However, CARB's persistent reliance on inconsistent and unreasonable data to overstate emissions benchmarks and understate technology feasibility challenges, collectively overestimating rulemaking benefits, as well as its adoption and enforcement of the rules prior to EPA's waiver determination have critically undermined the validity of these SORE amendments and EPA's subsequent authorization. As a result, OPEI continues to oppose the SORE amendments and EPA's authorization.
