It has been almost two weeks since the Environmental Protection Agency announced plans to ax Obama-era carbon emission regulations for new motor vehicles and engines, arguing that the agency didn’t have the authority to impose the science-based standards on the greenhouse gas emissions that the current administration says have only a negligible effect on climate change.
While Republican lawmakers and leaders in the fossil fuel and automotive industries support the move, Democratic Party leaders, health care industry and environmental groups are saying the decision goes against decades of peer-reviewed research that the heat-trapping gases will amplify climate change, and are taking legal action.
Supporter Spotlight
President Donald Trump and EPA Administrator Lee Zeldin announced Feb. 12 that the administration was rescinding its own findings, and, consequently, eliminating the greenhouse gas emission standards, or the legal limits on the amount of pollutants a vehicle can emit, that have been in place for more than 15 years.
“We are officially terminating the so-called Endangerment Finding, a disastrous Obama-era policy that severely damaged the American auto industry and massively drove up prices for American consumers,” Trump said during a press conference Feb. 12 at the White House. “Effective immediately, we’re repealing the ridiculous endangerment finding and terminating all additional green emission standards imposed unnecessarily on vehicle models and engines between 2012 and 2027 and beyond.”
The agency stated in a release that week that the Obama-era EPA, via section 202 of the Clean Air Act, exceeded its “authority to combat ‘air pollution’ that harms public health and welfare.” The EPA said that a policy decision of this magnitude should be up to Congress, and “even if the U.S. were to eliminate all GHG emissions from all vehicles, there would be no material impact on global climate indicators through 2100. Therefore, maintaining GHG emission standards is not necessary for EPA to fulfill its core mission of protecting human health and the environment, but regardless, is not within the authority Congress entrusted to EPA.”
When the action was announced, there was a torrent of criticism.
“Today, the Trump administration repealed the endangerment finding: the ruling that served as the basis for limits on tailpipe emissions and power plant rules. Without it, we’ll be less safe, less healthy and less able to fight climate change — all so the fossil fuel industry can make even more money,” former President Barack Obama said on social media Feb. 12.
Supporter Spotlight
Dr. Georges C. Benjamin, executive director of the American Public Health Association, said that the EPA’s action to repeal the endangerment finding that greenhouse gases threaten the health of all communities undermines decades of science and rulings by federal courts, including the U.S. Supreme Court.
“Instead of protecting the public’s health from the dangerous and deadly effects of air pollution, including greenhouse gases emitted by new cars and trucks, this action will exacerbate the health threats we are already seeing from climate change, including increased heat waves, more air pollution and deadly wildfires,” Benjamin said in a statement.
Dr. Gretchen Goldman, president and CEO of the Union of Concerned Scientists, said in a statement that Zeldin “took a chainsaw to the Endangerment Finding, undoing this long-standing, science-based finding on bogus grounds at the expense of our health. Ramming through this unlawful, destructive action at the behest of polluters is an obvious example of what happens when a corrupt administration and fossil fuel interests are allowed to run amok.”
Goldman continued that the science establishing harm to human health and the environment from heat-trapping emissions was clear in 2009.
“More than fifteen years later, the evidence has only mounted as have human suffering and economic damages. Meanwhile, the continued burning of fossil fuels is causing global warming emissions to rise. The science, the facts and the law are unassailable: EPA has the obligation and the authority to regulate this pollution under the Clean Air Act, an act of Congress it’s now blatantly violating,” she said. “The transportation sector is the single largest source of U.S. global heat-trapping emissions. By scrapping vehicle global warming pollution standards today, the Trump administration has co-signed the release of more than 7 billion tons of planet-warming emissions nationally in the decades ahead.”
The “Rescission of the Greenhouse Gas Endangerment Finding and Motor Vehicle Greenhouse Gas Emission Standards Under the Clean Air Act” was published Feb. 18 in the Federal Register.
The same day more than a dozen groups filed a lawsuit in the D.C. circuit against the EPA, “over its illegal determination that it is not responsible for protecting us from climate pollution and its elimination of rules to cut the tailpipe pollution fueling the climate crisis and harming people’s health,” the Environmental Defense Fund announced last week.
“The finding supported commonsense safeguards to cut that pollution, including from cars and trucks. In addition, the agency eliminated the clean vehicle standards, which were set to deliver the single biggest cut to U.S. carbon pollution in history, save lives, and save Americans hard-earned money on gas,” continued the Environmental Defense Fund.
Clean Air Act
The Clean Air Act has given the EPA comprehensive authority to set standards for and regulate motor vehicle pollution since it was signed by President Richard Nixon Dec. 31, 1970.
Section 202(a), states that the administrator “shall by regulation prescribe (and from time to time revise) in accordance with the provisions of this section, standards applicable to the emission of any air pollutant from any class or classes of new motor vehicles or new motor vehicle engines, which in his judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare.”
The act was amended in 1977 and 1990, expanding EPA authority.
In 2004, the agency initiated efforts to reduce greenhouse gas emissions. Then in 2007, in Massachusetts v. EPA, the Supreme Court found that greenhouse gases are air pollutants covered by the Clean Air Act.
By December 2009, the EPA had established the backbone for greenhouse gas emission rules with the final “Endangerment and Cause or Contribute Findings for Greenhouse Gases Under Section 202(a) of the Clean Air Act,” or the “endangerment finding.”
The EPA administrator had two conclusions: the “endangerment finding,” and the “cause or contribute finding.”
The endangerment finding that determined the current and projected concentrations of the six key well-mixed greenhouse gases — carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride — “in the atmosphere threaten the public health and welfare of current and future generations.”
The cause or contribute finding is that “the combined emissions of the six “well-mixed greenhouse gases from new motor vehicles and new motor vehicle engines contribute to the greenhouse gas pollution that threatens public health and welfare under CAA section 202(a).”
Rescission background
Rescinding the endangerment finding has been in the works for a year. Zeldin said in March 2025, that the agency was going to formally reconsider the 2009 endangerment finding and resulting regulations.
A fact sheet from the EPA explains that the agency was directed to review the legality and applicability of the endangerment finding.
“EPA carefully considered and reevaluated the legal foundation of the 2009 Endangerment Finding, the text of the CAA, and the Endangerment Finding’s legality in light of subsequent legal developments and court decisions,” the agency states. “The agency concludes that Section 202(a) of the CAA does not provide EPA statutory authority to prescribe motor vehicle emission standards for the purpose of addressing global climate change concerns. In the absence of such authority, the Endangerment Finding is not valid, and EPA cannot retain the regulations that resulted from it.”
Zeldin reiterated the argument during the Feb. 12 press conference, saying that Congress never voted for the climate mandates in section 202 of the Clean Air Act.
“If Congress wants EPA to regulate the heck out of greenhouse gasses emitted from motor vehicles, then Congress can clearly make that the law, which they haven’t done, for good reason,” Zeldin said at the press conference. “We have now realigned EPA rulemaking to reflect the Clean Air Act exactly as it is written and as Congress intended, not as others might wish it to be, where our predecessors focused on trying to make and please a few fear mongering climate alarmists.”
‘Exhaustive Precedent’
Around the time a public comment period opened on the findings, Dena Adler, senior attorney at the Institute for Policy Integrity out of the New York University School of Law, and legal fellow Kate Welty, issued a 19-page brief, “Exhaustive Precedent: EPA’s Requirement to Regulate Motor Vehicle Emissions that Contribute to Dangerous Air Pollution” in July 2025.
They explain that the current administration’s reasons for repealing the emission standards, stating that the “EPA’s suggestion that motor vehicle greenhouse gas emissions may not legally ‘contribute’ to climate change because they comprise a small share of global emissions rests on a flawed understanding of Section 202.”
They write that the Clean Air Act controls pollution from both stationary sources such as power plants and factories and mobile sources such as cars and trucks. Section 202 requires EPA to regulate emissions from new motor vehicles “if the Administrator finds that they ‘cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare.’”
The provision “authorizes EPA to regulate a variety of air emissions from new ‘motor vehicles,’ which encompasses cars, light-duty trucks (pick-up trucks and SUVs), heavy-duty trucks, buses, and motorcycles. Under this authority, EPA has been regulating air pollution from motor vehicles since the 1970s,” they continue.
With the 1977 revisions to the Clean Air Act, “Congress wanted EPA to consider how each source of emissions contributed to public health dangers, not limit the agency to regulating only source categories that emitted enough pollution to independently cause health harms,” Adler and Welty explain. “Any effort by EPA to now require that greenhouse gas emissions from new motor vehicles independently endanger public health and welfare would contradict the express Congressional intention described in the legislative history.”
Adler and Welty note that, in 2009, when the EPA concluded that greenhouse gas emissions endanger public health and welfare and that the greenhouse gas emissions from new motor vehicles contribute to climate change, “the agency found that new motor vehicles were responsible for over 23 percent of all U.S. greenhouse gas emissions and approximately 4 percent of all greenhouse gas emissions worldwide and concluded that either comparison was sufficient to meet the contribution standard of Section 202(a).”
In the time since, nothing has meaningfully changed to disturb this finding, as motor vehicles remain responsible for more than 23% of all U.S. greenhouse gas emissions, and greenhouse gas emissions from new motor vehicles “still make a meaningful contribution to climate change and unquestionably cause substantial damages in and of themselves. They also far surpass the levels of contribution that EPA has consistently recognized as sufficient to justify regulation in the past,” they wrote.
“The scale of greenhouse gas emissions from motor vehicles, EPA’s regulatory precedents under Section 202, and its reasoning under analogous Clean Air Act provisions all demonstrate that emissions from motor vehicles contribute to dangerous air pollution.”
Coastal effects
Southern Environmental Law Center Climate Analyst Jenny Brennan told Coastal Review last week that the lift of the endangerment finding “will almost certainly result in the worsening of climate change impacts that North Carolina communities are already struggling with — meaning sea level rise at faster rates, more rainstorms that drop massive amounts of water in just a few hours, and heatwaves that make it difficult for people to stay safe and healthy.”
Brennan continued that all these impacts will add stress to the already taxed infrastructure, such as roads, drainage systems and housing.
“Extreme heatwaves with even more air pollution, which is likely in the absence of the air regulation policies based on the endangerment finding, pose an even greater health hazard; heat plus air pollution makes it harder for even healthy people to breathe and is especially dangerous to people with asthma, heart conditions, or other medical conditions,” Brennan said.
