Clean Air Act reform bills may be on the move: Mostly good, one bad

There are more Clean Air Act (CAA) bills that could be on the move in the House.

Tomorrow, the House Energy and Commerce Committee’s Environment Subcommittee is scheduled to hold a hearing on several CAA bills.

Most of these bills are good reforms. One exception, however, is the Diesel Emissions Reduction Act of 2025 (H.R. 2140). The following highlights two notable reform bills and explains concerns with the Diesel Emissions Reduction Act of 2025.

Choice in Automobile Retail Sales Act (H.R. 2165)
Sponsor: Tim Walberg (R-MI)

In 2023, the House passed legislation known as the CARS Act. A new version of the CARS Act is now making its way through the House.

Should the EPA be able to dictate what kind of cars people drive? Of course not.

The CARS Act prohibits the EPA from using tailpipe regulations to limit the availability of new motor vehicles. Specifically, the language states that the agency may not develop rules that:

(i) mandate the use of any specific technology; or

(ii) result in limited availability of new motor vehicles based on the type of new motor vehicle engine in such new motor vehicles.

This new version of the CARS Act appears identical to the 2023 bill except the 2023 version included a prohibition on the then-proposed Biden tailpipe rule from being finalized, implemented, or enforced. This is a moot issue now, so the new version doesn’t include this language.

Unless legislators think the government should reduce consumer choice and help force people into electric vehicles, this bill should be easy to support. In fact, back in 2023, the House passed the CARS Act in a bipartisan manner. Hopefully, there will be even more bipartisan support this year. 


State Emissions Authority Act of 2026 (No bill number yet)
Sponsor: Rep. Glenn Grothman (R-WI)

The National Ambient Air Quality Standards (NAAQS) are federal air quality standards for the six criteria pollutants: carbon monoxide, lead, nitrogen dioxide, ozone, particulate matter, and sulfur dioxide. States are expected to develop plans to meet these standards.

The standards are extremely stringent, and most states struggle to meet them all. Therefore, they have every incentive to find effective ways to meet the requirements.

Yet the CAA still requires states to have vehicle inspection and maintenance programs for certain nonattainment areas. This makes no sense. Vehicles rarely fail emissions tests, particularly new vehicles. In Rep. Grothman’s home state of Wisconsin, only 3.1 percent of vehicles failed emissions tests according to the 2021 Wisconsin Vehicle Inspection Program Annual Report.

Despite the low failure rate and the costs to state taxpayers and drivers, the federal vehicle inspection and maintenance requirements remain in place.

The State Emissions Authority Act of 2026 would get rid of these federal mandates. This doesn’t mean that states won’t keep these programs. They will if they think it makes sense. But this choice should be left to the states as they figure out the best ways to meet federal air quality standards.


Diesel Emissions Reduction Act of 2025 (H.R. 2140)
Sponsors: Reps. Doris Matsui (D-CA) and Nick Langworthy (R-NY)

This bill would reauthorize the Diesel Emissions Reduction Act through 2029.

CEI has argued that the Diesel Emissions Reduction Act, which was enacted in 2005, needs to be repealed. In CEI’s Modernizing the EPA: A Blueprint for Congress, we discussed how the EPA has been spending taxpayer dollars to lead a shift towards electric vehicles and equipment. This includes the Diesel Emissions Reduction Act. The Blueprint explains:

Congress passed the Diesel Emissions Reduction Act in 2005, giving the EPA authority, as the agency states, “to accelerate the upgrade, retrofit, and turnover of the legacy diesel fleet.” Some of this money has gone to the push for electrification, such as electrifying parking spaces and buying electric tractors. This program is broad in scope and covers everything from port equipment, school buses, to locomotives.

This program, among others, has played a pivotal role in the left’s electrification agenda. The Blueprint argues:

These programs fail to properly consider costs, the unreliability of electric vehicles, and infrastructure obstacles. They do not respect the decisions made by local governments, businesses, or other buyers to make the best vehicle and equipment choices to meet their needs. Further, the buyers of the vehicles and equipment should not be subsidized in these purchases.

The Trump administration’s fiscal year 2027 budget calls for eliminating the Diesel Emissions Reduction Act program. The budget explains:

Diesel Emissions Reduction Act (DERA) Grants. The Budget again proposes to eliminate this unnecessary and wasteful program, saving taxpayers $90 million. These grants are an unfair handout using taxpayer dollars. Grants under DERA distort the market by subsidizing select technologies, picking winners, and subverting consumer choice, such as:

– $2 million to San Diego to purchase an electric tug boat;
– $9 million to buy electric buses for Central Florida Regional Transportation Authority;
– $518,000 to Goodwill Industries of New Mexico to cover 45 percent of the cost to buy electric semitruck tractors.

The Republican Study Committee’s FY 2025 Budget Proposal calls to:

Eliminate Diesel Emissions Reduction Act Grants

Grants made under Diesel Emissions Reduction Act (DERA) have gone to wasteful projects involving cherry pickers, electrifying parking spaces at rest stops, and retrofitting old tractors. DERA grants are wasteful, do nothing to protect the environment, and should be eliminated.  

Conservatives have frequently opposed the Green New Deal and the efforts to electrify vehicles. The One Big Beautiful Bill Act, which repealed and phased out many Inflation Reduction Act (IRA) Green New Deal subsidies, included the repeal of the IRA’s diesel emission reduction grants.

Lawmakers who supported the One Big Beautiful Bill Act correctly recognized that the far left is trying to achieve its radical climate agenda through spending and not just through regulations. To fight this, lawmakers must confront both regulatory overreach and spending.

The Diesel Emissions Reduction Act of 2025 undermines such efforts. It enables the Green New Deal agenda, undermines consumer choice, and uses subsidies to distort the marketplace. The grants issued during the program’s history are enlightening.

Conclusion
 
The Environment Subcommittee is reviewing  many worthwhile CAA reforms. Besides the two bills discussed, there are others such as a bill that would prohibit restrictions on engine idling for certain buses and legislation that would rescind requirements that promote or require engine idle start-stop technology. Hopefully, the good policy will easily make it through the subcommittee.