Decreasing greenhouse gas emissions and increasing resilience to climate impacts involve use of existing environmental, natural resource, and land use laws. They also demand creation of new approaches. Our current efforts focus on federal, state, and local laws and regulations related to air pollution; environmental impact assessment; public lands management; and zoning and land use controls.
Clean Air Act
The Clean Air Act (CAA) has historically served as the primary basis for federal regulation of greenhouse gas emissions in the U.S. Recently, however, the second Trump Administration has moved to roll-back greenhouse gas regulations adopted under the CAA. These efforts are recorded in the Sabin Center’s Climate Backtracker.
The Sabin Center conducts research on legal issues relating to the use of the CAA to regulate greenhouse gas emissions and participates in relevant regulatory proceedings.
The so-called “Endangerment Finding” – a 2009 finding by the Environmental Protection Agency (EPA) that six key greenhouse gases threaten public health and welfare–provides the foundation for regulation of emissions of those gases under the Clean Air Act. The Sabin Center is working to defend that finding against attacks by the second Trump administration, which has proposed to repeal it. The Sabin Center filed comments on the proposed repeal and supported cities and local governments to do so by providing a template comment letter for their use.
Engagement
- Sabin Center Comments on EPA's Proposed Rule to Reconsider the Endangerment Finding and Vehicle GHG Standards, Submitted with U.S. Conference of Mayors, National League of Cities, Climate Mayors and C40 Cities (submitted September 22, 2025)
- Second Sabin Center Comments on EPA’s Proposed Rule to Reconsider the Endangerment Finding and Vehicle GHG Standards (submitted September 19, 2025)
- Template Letter on EPA's Proposed Endangerment Finding Rollback for Local Government Use (shared August 28, 2025)
In 2015, EPA published two final rules under section 111 of the CAA, establishing carbon dioxide emissions limits for new and existing fossil fuel power plants. During the first Trump administration, the rules were significantly weakened. The Biden administration adopted stronger rules, which the second Trump administration is now seeking to weaken again. The Sabin Center has been active in regulatory proceedings and litigation regarding the power plant rules. Much of our engagement has focused on supporting parts of the rules that set emissions limits based on the use of carbon capture and storage technologies.
Legal Briefs
Amicus Brief on behalf of the National League of Cities and the U.S. Conference of Mayors in Support of EPA in West Virginia v. EPA, by Michael Burger, Amy Turner, and Vincent Nolette (October 2024)
The Sabin Center filed an amicus brief on behalf of the National League of Cities and the U.S. Conference of Mayors in support of EPA in West Virginia v. EPA, the lawsuit challenging the EPA’s 2024 Power Plant Rules. The brief highlights the climate impacts that cities already experience, and local governments' efforts to mitigate and adapt to climate change.
Amicus Brief on behalf of Carbon Capture and Storage Scientists and Engineers in Support of EPA in West Virginia v. EPA, by Michael Burger and Romany Webb, with contributions from Olivia Guarna (October 2024)
The Sabin Center filed an amicus brief on behalf of Carbon Capture and Storage scientists and engineers in support of Respondent EPA in West Virginia v. EPA, which is a challenge to EPA's recent rules on greenhouse gas emissions from fossil fuel power plants.
Amicus Brief on behalf of Local Governments in West Virginia v. EPA by Michael Burger (January 2022)
The Sabin Center filed an amicus brief on behalf of the National League of Cities and the U.S. Conference of Mayors in West Virginia v. EPA, a case that is currently before the United States Supreme Court. The case concerns the scope of the United States Environmental Protection Agency’s (EPA) authority to regulate greenhouse gas emissions from existing fossil fuel power plants under Section 111(d) of the Clean Air Act (CAA). The brief argues that significant federal regulation of power plants’ emissions is necessary to support and supplement local climate action, that Section 111(d) does not foreclose generation-shifting regulation, and that neither the major questions doctrine nor the federalism clear statement canon are implicated by the case.
Amicus Brief on behalf of Local Governments in American Lung Association v. EPA by Michael Burger and Hillary Aidun (April 2020)
The Sabin Center filed an amicus brief on behalf of local governments in support of state and environmental petitioners in American Lung Association v. EPA, the lawsuit challenging the Environmental Protection Agency's repeal of the Clean Power Plan and its replacement, the Affordable Clean Energy Rule. The brief highlights the climate impacts that cities are already facing, and local governments' efforts to mitigate and adapt to climate change. The coalition members include the U.S. Conference of Mayors, the National League of Cities, and 23 cities, towns, counties and mayors representing over 12 million residents.
Amicus Brief on behalf of Carbon Capture and Storage Scientists and Engineers in North Dakota v. EPA, Michael Burger and Jessica Wentz (December 2016)
This amicus brief was written on behalf of eleven carbon capture and storage (“CCS”) experts in support of EPA’s emission standard for new coal-fired power plants. The standard is based on the CO2 emission reductions that can be achieved through the implementation of partial CCS, and one of the central issues in the case is whether CCS technologies are adequately demonstrated and available for installation at coal-fired power plants. The brief contains ample evidence corroborating EPA’s determination that these technologies are an adequately demonstrated system of emissions reduction for new coal-fired power plants.
Amicus Brief on behalf of Local Governments in West Virginia v. EPA, Michael Burger and Justin Gundlach, and related Press Release (April 2016)
More than 50 city and county governments from 28 states, together with The U.S. Conference of Mayors (USCM), the National League of Cities (NLC), and the mayors of Dallas, Knoxville, and Orlando have signed an amicus brief explaining why the U.S. Environmental Protection Agency’s Clean Power Plan is critical to the safety and economic security of local communities across the United States. The brief was authored by the Sabin Center for Climate Change Law at Columbia Law School.
See also: Amicus Motion on Behalf of Cities in Support of EPA’s Clean Power Plan by Michael Burger and Justin Gundlach, December 2015
Regulatory Engagement
- Comments on EPA's Proposed Rule to Repeal GHG Performance Standards for Power Plants, Submitted with Climate Mayors and C40 Cities (submitted August 7, 2025)
- Comments on EPA's Proposed Rule to Repeal GHG Performance Standards for Power Plants Based on CCS System (submitted August 7, 2025)
- Comments on EPA's Proposed Rule to Repeal GHG Performance Standards for Power Plants (submitted August 6, 2025)
- Comments on EPA’s Proposed Revisions to the Power Sector New Source Performance Standards (submitted March 18, 2019)
- Comments on EPA’s Proposed Repeal of the Clean Power Plan (submitted April 18, 2018)
The Sabin Center has explored the legal and policy rationales for regulating greenhouse gas emissions under section 115 of the CAA – the International Air Pollution provision. This provision authorizes EPA to require states to address emissions that contribute to air pollution endangering public health or welfare in other countries, if the other countries provide the U.S. with reciprocal protections. In so doing, it provides the executive branch of the U.S. government with the authority, procedures, and mechanisms to work with the states and private sector to take national climate action. Action under the provision could increase administrative efficiency and reduce burdens on regulated companies. If combined with new legislation with Congress it could help fill any emissions gap between the nation's emissions trajectory and the goal of limiting global warming to 1.5 C..
Learn more here.