S-4931-119
Read twice and referred to the Committee on Environment and Public Works.
Sponsored by Mike Lee (R-UT)
What it does
This bill would amend the Clean Air Act to prohibit the EPA from issuing any regulation — including waivers — that can "reasonably be determined" to restrict vehicle or engine types (including internal combustion engines), require fuel-switching at power plants, reduce electric grid reliability, mandate commercially unavailable or cost-prohibitive technology, or "significantly expand" EPA authority beyond congressional intent. These restrictions would apply to all EPA rulemaking under the Clean Air Act going forward.
Who benefits
Automakers that produce internal combustion engine vehicles and their dealership networks. Oil and gas companies whose products power those vehicles. Coal and natural gas power plant operators who would face fewer mandates to switch fuels. Electricity ratepayers in regions where compliance costs might otherwise raise rates. Rural and lower-income consumers who may have fewer options to transition to electric vehicles. Manufacturers and industries that rely on existing, proven technologies rather than emerging ones.
Who is hurt
Electric vehicle manufacturers and their supply chains, who would lose a regulatory environment that may have favored EV adoption. Renewable energy companies that compete with fossil fuel power plants. Communities near power plants or in high-pollution areas who may see fewer emissions reductions. Public health researchers and advocates who argue air quality standards reduce illness and mortality. States like California that have historically received EPA waivers to set stricter vehicle emissions standards, which this bill could block. Workers in clean energy industries that depend on regulatory demand for their products.
Supporters argue
Supporters argue that the EPA has repeatedly exceeded its statutory authority — a concern validated by the Supreme Court in West Virginia v. EPA (2022), which blocked the agency's generation-shifting Clean Power Plan. They contend that unelected regulators should not effectively ban internal combustion engines or mandate fuel-switching without explicit congressional authorization, and that such sweeping decisions affecting millions of consumers and the reliability of the electric grid belong to elected lawmakers, not agency officials. They further argue that requiring commercially unavailable or cost-prohibitive technology imposes real economic harm on businesses and consumers without guaranteed environmental benefit.
Opponents argue
Opponents argue that the bill's broad, vague prohibitions — such as any rule that "can reasonably be determined" to restrict vehicle types or "significantly expand" EPA authority — would effectively paralyze the agency's core mission under the Clean Air Act, including regulations that have reduced smog, particulate matter, and other pollutants linked to respiratory disease. They contend that terms like "cost-prohibitive" and "practically infeasible" lack clear definitions and would invite endless litigation, and that blocking California's longstanding waiver authority would override a 50-year precedent explicitly written into the Clean Air Act. They also argue the bill could roll back rules that have already driven measurable improvements in air quality.
Constitutional context
West Virginia v. EPA (2022) established that agencies must have clear congressional authorization for rules of vast economic and political significance — this bill responds directly to that doctrine by restricting EPA authority at the statutory level. Post-Loper Bright (2024), courts independently review agency statutory interpretations, meaning the bill's broad and undefined terms (e.g., "reasonably be determined," "significantly expand") would themselves face independent judicial scrutiny rather than deferential review.
Checks and balances
Congress would gain authority by constraining EPA's rulemaking power; the EPA (executive branch) loses discretion it currently exercises under the Clean Air Act. Courts would serve as the primary check, adjudicating disputes over whether specific regulations fall within the bill's broad prohibitions — a role expanded by the end of Chevron deference under Loper Bright (2024).
Historical precedent
The Supreme Court's stay and subsequent invalidation of the EPA's Clean Power Plan in West Virginia v. EPA (2022) addressed similar questions about EPA authority to mandate generation-shifting at power plants under the Clean Air Act.