In a significant policy shift, U.S. Transportation Secretary Sean P. Duffy announced the elimination of a Biden-era rule that required states to measure and set targets for reducing greenhouse gas (GHG) emissions from vehicles on federally funded highways. The decision, announced on April 18, 2025, marks the first major deregulatory action of the second Trump administration.
The original rule, reinstated during President Biden’s tenure, aimed to align state transportation planning with national climate objectives by mandating the tracking and reduction of CO₂ emissions from highway travel. However, Secretary Duffy criticized the regulation as an overreach, stating it imposed unnecessary costs and diverted resources from essential infrastructure projects.
“I slashed this ridiculous climate requirement to ensure no radical political agenda gets in the way of revitalizing America’s highways,” Duffy remarked, emphasizing a focus on traditional infrastructure development over climate-related mandates.
Industry groups have expressed support for the repeal. Jim Tymon, executive director of the American Association of State Highway and Transportation Officials, noted that the GHG measure was considered but ultimately excluded from the 2021 Infrastructure Investment and Jobs Act. Similarly, Dave Bauer, president and CEO of the American Road & Transportation Builders Association, praised the move for removing what he termed an “unnecessary, ideologically driven mandate.”
Critics of the repeal argue that eliminating the GHG rule undermines efforts to address climate change and could hinder progress toward reducing transportation-related emissions. Environmental advocates stress the importance of integrating climate considerations into infrastructure planning to ensure long-term sustainability and resilience.
The decision aligns with a broader trend within the current administration to roll back climate-focused policies. Earlier actions include the reversal of fuel economy standards for vehicles and the rescinding of memos that prioritized climate and equity in infrastructure projects.
