Overview
The American Public Health Association recently issued a public statement condemning the Environmental Protection Agency’s proposal to repeal all greenhouse gas emissions standards for motor vehicles. Public comments on the proposal end on September 2, 2025. All manner of people, from members of Moms Clean Air Force to members of Congress, have signed up to testify during the four days of virtual public hearings, August 19 – 22.
The “well-mixed greenhouse gases” include carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride. According to the EPA, the endangerment finding was “based on careful consideration of the full weight of scientific evidence and a thorough review of numerous public comments received on the Proposed Findings.” It presented the factual basis which gave rise to EPA’s statutory duty to issue national outdoor air quality standards for the well-mixed greenhouse gases. Since that time, the 2009 endangerment finding was incorporated and built upon in subsequent endangerment findings for power plants, oil and natural gas operations, and aircraft.
EPA Seeks to Repeal the Endangerment Finding and Related Regulations
On January 20, 2025, President Trump issued Executive Order 14154, which directed the Administrator of the EPA to make recommendations on the legality and continuing applicability of the endangerment finding. On July 29, 2025, the EPA announced its proposal to rescind the endangerment finding and repeal all greenhouse gas emissions standards for motor vehicles. On the same day, the American Lung Association and the American Public Health Association issued public statements opposing repeal.
A proposed rule was published in the Federal Register on August 1, 2025. Comments were initially due by September 15, and the deadline was extended to September 22. Simultaneously with this announcement, the EPA published notice of the availability of a new report, A Critical Review of Impacts of Greenhouse Gas Emissions on the U.S. Climate, which was prepared by five people selected by the Secretary of Energy. (For comparison, the Fifth National Climate Assessment released in 2023 was prepared by over 500 authors, as well as 250 technical contributors.) On August 1, 2025, the EPA published notice of the availability of the Critical Review report and invited public comment, with a 30 day comment period ending on September 2, 2025, the day after Labor Day. The sequence of events suggests an administration opposed to government regulation in principle, more than it suggests a change in the evidence.
Opportunities to Act to Uphold the Endangerment Finding in the Rulemaking Process
The evidence that greenhouse gas emissions endanger public health and welfare has only grown more compelling since 2009. Additionally, more and more Americans have directly experienced climate-exacerbated natural disaster, whether hurricanes or wildfires or extreme heat. In response to the Critical Review report and proposed rescission of the endangerment finding, the National Academies of Science, Engineering, and Medicine have launched a fast track study of evidence related to climate change and health that has accrued since the 2009 endangerment finding. The study aims to provide an authoritative summary of consensus views on the current state of climate science. It will “examine how current understanding compares to the 2009 Endangerment Finding, and provide explanation for any changes. The study will develop conclusions that describe supporting evidence, the level of confidence, and areas of disagreement or unknowns.”
The National Academies have issued a request for information asking that respondents submit peer-reviewed articles, white papers, technical reports, or other comments relevant to the study by August 27. The National Academies report will be completed and publicly released in September, with an explicit goal of informing the EPA’s rulemaking process.
The rulemaking process includes 4 days of virtual public hearings, on August 19 – 22. All manner of people, from members of Moms Clean Air Force and the Alliance of Nurses for a Healthy Environment to members of Congress, have signed up to testify.
For anyone who decides to submit written comments on either the Critical Review report or the proposed rescission of the endangerment finding, the potential arguments include arguments related to the factual inaccuracies of the Critical Review, as well as arguments related to the procedural requirements of the Administrative Procedure Act , the lack of consideration for regulatory costs to be found in the text of the Clean Air Act , and prior court opinions which have acknowledged the widely-recognized harms of climate change and the soundness of climate science.
The proposed rescission of the 2009 endangerment finding is a critical test of whether the federal government will adhere to evidence-based decision-making, and the public health community has the opportunity to help ensure that it passes the test and upholds this cornerstone of federal efforts to protect public health from the devastating effects of climate change.
This post was written by Jill Krueger, Director, Climate and Health, Network for Public Health Law. The Network for Public Health Law provides information and technical assistance on issues related to public health. The legal information and assistance provided in this document do not constitute legal advice or legal representation. For legal advice, readers should consult a lawyer in their state.
Support for the Network is provided by the Robert Wood Johnson Foundation (RWJF). The views expressed in this post do not represent the views of (and should not be attributed to) RWJF.
