EPA Plans to Rescind the 2009 Greenhouse Gas Endangerment Finding. Here’s What States Need to Know.

EPA Administrator Lee Zeldin recently announced a proposed federal rule rolling back the 2009 Greenhouse Gas Endangerment Finding and limiting its own power to regulate greenhouse gases from motor vehicles.

This is a significant development because the way policymakers interpret the Clean Air Act (CAA) not only sets precedents for the scope of federal power in addressing environmental challenges, but also directly shapes the balance of authority between states and the federal government.

The CAA has stood for over six decades as one of the most consequential environmental laws in the United States. Over time, the CAA increasingly tilted the scales in the federal government’s favor, especially at the EPA, to take on an outsized enforcement role exemplified by the 2009 Endangerment Finding, leading to a governance structure that restricted state autonomy and placed regulatory burdens on local industries and consumers.

From 1963 to Today: The Evolution of the Clean Air Act and the 2009 Endangerment Finding

Passed in 1963, the Clean Air Act was designed to control air pollution and to protect public health. Since its original enactment, the law has been amended several times, in 1970, 1977, and 1990, expanding its scope to include the establishment of National Ambient Air Quality Standards (NAAQS), State Implementation Plans (SIPs), emission standards, inspection and maintenance programs, and even penalties for non-compliance.

However, there was a major turning point in 2007, when the U.S. Supreme Court ruled in Massachusetts v. EPA, 549 U.S. 497 (2007) that greenhouse gases (GHGs), including carbon dioxide, fall within the definition of “air pollutants” under the Clean Air Act. This decision expanded the EPA’s authority to regulate GHG emissions from new motor vehicles pursuant to Section 202(a) of the Act.

The Court further held that the EPA is obligated to evaluate whether such emissions may reasonably be anticipated to endanger public health or welfare—a process known as an “endangerment finding.” If the EPA makes such a finding, it is legally required to regulate the emissions in question.

In 2009, the Obama EPA followed through and issued an Endangerment Finding, determining that the current and projected concentrations of the six key greenhouse gases pose a threat to public health and welfare. When combined with the Cause or Contribute Finding, this move triggered the EPA’s Section 202(a) powers under the Clean Air Act to impose sweeping regulations on emissions from new motor vehicles and engines, enabling the government’s ability to strictly regulate cars and vehicle engine emissions.

These new regulations distorted the marketplace and resulted in immense compliance costs for engine and auto manufacturers, ultimately driving up vehicle prices for average consumers and businesses who rely on cars and trucks to go about their day.

The Trump EPA’s Challenge: Reinterpreting Authority

The Trump Administration has now taken preliminary steps to rescind the 2009 Endangerment Finding and, therefore, repeal these regulations on vehicle greenhouse gas emissions.

Once the rule is finalized, the proposal would eliminate future obligations for automakers and engine manufacturers to measure, control, or report GHG emissions from highway vehicles, including retroactively for model years produced prior to the rule change. The EPA will continue to uphold existing requirements related to criteria pollutants, air toxins, Corporate Average Fuel Economy (CAFE) testing, and associated labeling standards as required by the Clean Air Act.

As the EPA explained in its justification, this change in policy would end the status quo where internal combustion engines are singled out and penalized under current law. Rescinding the Endangerment Finding would instead usher in a return to market competition and require auto manufacturers to respond to consumer demand, resulting in a “composition of [light duty] vehicles that is closer to consumer needs and preferences.”

Consumers ultimately benefit when industry must compete on a fair and level playing field, resulting in lower prices and greater choice in the marketplace.

Restoring the Balance of Power: Federal vs. State Authority

Recent Supreme Court decisions highlight the urgent need to reassess the scope of unelected bureaucratic power and guard against government overreach.

In Loper Bright, the Court decisively reaffirmed judicial authority over unelected officials, strengthening the separation of powers and ensuring accountability across all three branches of government. Courts are now not only able to conduct de novo reviews of agency rules but are also better equipped to push back when federal agencies exceed their authority, reinforcing the judiciary’s role as a check on executive power as the framers of the Constitution intended.

Equally significant, West Virginia v. EPA was a huge win for the states. It puts the brakes on federal overreach, making clear that federal agencies can’t rewrite energy and industry policy on their own. For states, this case goes beyond legal technicalities—it protects local economies, safeguards industries, and preserves the freedom to govern without unelected bureaucrats in Washington dictating every decision.

Together, these rulings send a powerful message: the balance of power between citizens, states, and the federal government cannot be ignored. While the judiciary acts as a guardian against unchecked bureaucratic authority, the executive branch must also exercise restraint to protect individual liberty.

Considerations for States

For well over a decade, ALEC has chronicled the EPA’s assault on state sovereignty under the Obama and Biden Administrations. Congress originally intended for the EPA to cooperate with states on a balanced and level playing field, but under progressive leadership, the agency has been repeatedly weaponized against states and localities.

States should pursue a balanced approach that combines free markets, limited government, and environmental protection to live up to the original intent of the Clean Air Act and the Clean Water Act. ALEC’s model Resolution on Environmental and Economic Stewardship encourages federal and state governments to support technological innovation and market competition in the private sector that will lead to broadly supported climate and environmental policy solutions.

Secretary of Energy Chris Wright noted in a recent report, climate change is a challenge, not a catastrophe. Only by fostering American ingenuity and innovation can we succeed in delivering affordable, reliable, and clean energy in a way that strengthens the economy and respects the environment at the same time.

Bureaucratic overreach at the EPA kneecaps hardworking U.S. families and businesses with artificially high utility bills, a constrained vehicle marketplace, and increased costs across the entire economy. Thankfully, Administrator Zeldin’s effort to rescind the 2009 Endangerment Finding is a promising start to recalibrating America’s energy policy.