A group comprising health and environmental organizations filed a lawsuit against the EPA on Wednesday, contesting the reversal of a critical scientific determination that has served as the cornerstone for U.S. efforts to regulate greenhouse gas emissions and combat climate change. The EPA recently issued a rule that rescinded a 2009 government declaration, known as the endangerment finding, which established that carbon dioxide and other greenhouse gases pose a threat to public health and welfare.
The endangerment finding from the Obama era forms the legal basis for almost all climate regulations under the U.S. Clean Air Act, encompassing regulations for motor vehicles, power plants, and other sources of pollution contributing to global warming. By revoking this finding, all greenhouse gas emission standards for vehicles have been eliminated, potentially leading to a wider rollback of climate regulations affecting stationary sources like power plants and oil and gas facilities, according to experts.
The legal challenge, filed in the U.S. Court of Appeals for the District of Columbia Circuit, argues that the EPA’s decision to rescind the endangerment finding is unlawful. The lawsuit contends that the 2009 finding supported essential measures to reduce climate pollution, particularly from cars and trucks. The coalition behind the lawsuit highlighted that the clean vehicle standards established by the Biden administration were poised to deliver significant reductions in U.S. carbon emissions, save lives, and reduce fuel costs for Americans.
Brian Lynk, a senior attorney at the Environmental Law & Policy Center, emphasized that after nearly two decades of scientific support for the 2009 finding, it is implausible for the EPA to dismiss this body of evidence as incorrect. Lynk criticized the decision as reckless and legally unsustainable, warning that it introduces immediate uncertainty for businesses, ensures prolonged legal disputes, and undermines the stability of federal climate regulations.
The lawsuit involves various organizations, including the American Public Health Association, American Lung Association, Alliance of Nurses for a Healthy Environment, Physicians for Social Responsibility, and environmental groups like the Center for Biological Diversity, Conservation Law Foundation, Environmental Defense Fund, Natural Resources Defense Council, and Sierra Club. The suit names the EPA and its administrator Lee Zeldin as defendants.
President Donald Trump and Administrator Zeldin have defended the repeal of the endangerment finding, framing it as a significant deregulatory measure that liberated sectors of the economy from burdensome regulations. Environmental groups have strongly opposed the move, labeling it as a major setback in the fight against climate change and emphasizing the increasing strength of the scientific evidence supporting the endangerment finding over the years.
The Clean Air Act mandates the EPA to regulate emissions of any air pollutant that may endanger public health or welfare. Following a Supreme Court ruling in 2007, the EPA determined in 2009 that greenhouse gases like carbon dioxide fall under this regulatory framework, leading to the implementation of new vehicle standards and subsequent regulations. Critics argue that the repeal of the endangerment finding, coupled with the relaxation of vehicle emission controls, contradicts the EPA’s mission to safeguard public health and contravenes its obligations under the Clean Air Act.
Gretchen Goldman, president and CEO of the Union of Concerned Scientists, part of the legal action, condemned the decision as a dangerous departure from scientific facts and public interest. She highlighted the rising heat-trapping emissions and global temperatures due to fossil fuel combustion, underscoring the mounting human and economic consequences worldwide.