September 23, 2025

ELPC Stands Up for Science, Fights to Protect the Endangerment Finding

The proposal to rescind the Endangerment Finding is unlawful, arbitrary and capricious, and contrary to sound science. It should be withdrawn.

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On September 22nd, ELPC took a stand in one of our nation’s most consequential environmental battles – the Trump administration Environmental Protection Agency’s (EPA) proposal to undo the 2009 “Endangerment Finding,” the scientific basis for key greenhouse gas regulations from motor vehicles and other sources.  

ELPC, on behalf of itself and the Hoosier Environmental Council, Illinois Environmental Council, Iowa Environmental Council, Minnesota Environmental Partnership, and Ohio Environmental Council (collectively the Midwest Environmental Advocates), submitted comments to EPA challenging the unlawful and misguided attempt to overturn this long-standing, science-backed finding. 

As described further in the comments, ELPC pointed out three flawed premises that EPA’s proposal to abandon the 2009 Endangerment Finding rests on.  

1. The proposal relies on the false premise that greenhouse gas pollution does not contribute to climate change despite EPA’s own prior conclusion in its 2009 Finding that greenhouse gas pollution from power plants and vehicles harms public health and welfare. The scientific data developed since 2009 has only reinforced this conclusion. 
2. EPA’s proposal argues that motor vehicle greenhouse gas emissions are not “air pollutants” subject to regulation. EPA further mischaracterizes the Endangerment Finding, which concluded that these emissions harm health and welfare nationwide. This ignores decades of agency practice and Supreme Court precedent dating back to 2009.
3. EPA argues that it can withdraw the Endangerment Finding and abandon any Clean Air Act (CAA) regulation of greenhouse gases, but that the Act would still block other remedies for climate harm under federal common law or state climate law. This is legally indefensible. 

For these reasons, the proposal to rescind the Endangerment Finding is unlawful, arbitrary and capricious, and contrary to sound science. It should be withdrawn. 

READ THE COMMENTS 

Highlights from ELPC’s comments: 

• EPA properly determined in 2009 that greenhouse gas emissions contribute to air pollution that endangers public health and welfare: EPA based its conclusions on sound science and peer-reviewed reports of thousands of studies related to climate change science and assessing the impacts of climate change. 

• Recent studies and assessments continue to strengthen the scientific basis for EPA’s 2009 Endangerment Finding: In just the past few years, evidence of human-driven climate change has grown stronger, and its impacts have worsened. Nearly every single health impact attribution study conducted in the last decade has reported “a substantial negative health impact of climate change—most often, loss of life due to rising temperatures or extreme weather.” 

• EPA’s rationale for the proposal is severely flawed, and unsupported by the law and the record: EPA backpedaled from the robust, peer-reviewed body of sound scientific literature underlying the Endangerment Finding and now relies almost exclusively on a biased and rushed draft report of a so-called “Climate Working Group” (CWG). The CWG report was written in secret by five hand-picked, well-known skeptics of the impacts of climate change and manipulates data to serve a pre-determined purpose.  

• Despite EPA arguing otherwise, greenhouse gases are “air pollutants” that cause or contribute to harmful “air pollution” within the meaning of the CAA: EPA’s rationale misconstrues both the text of the CAA and its historical implementation. The CAA plainly includes greenhouse gases within the meaning of the terms “air pollutant” and “air pollution.” 

• EPA identifies no valid basis to rescind its 2009 “Endangerment” and “Cause or Contribute Findings”: EPA attempts to argue that its own findings in 2009 were not consistent with the language in the CAA, but its proposal did not identify any valid grounds for EPA to refrain from finding that new emissions cause or contribute to endangerment of human health. 

• EPA proposes to treat the term “welfare” as encompassing questions of cost of compliance or effectiveness of controls: The 2009 Endangerment Finding properly focused on public health and welfare effects of motor vehicle pollution independently from factors that guide emissions standards. 

• The 2009 Finding presents no “major question”: EPA questions its own authority to issue the Endangerment Finding by citing the “major question” doctrine, which restricts administrative agencies from making decisions on issues of significant importance without clear congressional authorization. However, the 2009 Endangerment Finding makes a judgement that the Supreme Court held in no uncertain terms that EPA was required to make under the CAA.