Attorney General Clark Files Lawsuit to Fight Greenhouse Gas Emissions

Attorney General Charity Clark today joined a coalition of 18 other attorneys general in filing a lawsuit against the U.S. Environmental Protection Agency (EPA) challenging a rule that would weaken regulations designed to phase out the use of hydrofluorocarbons (HFCs) in commercial equipment. HFCs are chemicals used for refrigeration and cooling that are up to 10,000 times more potent than the equivalent amount of carbon dioxide, and they are among the fastest growing sources of greenhouse gas emissions both in the United States and around the world. In the petition filed today in the U.S. Court of Appeals for the District of Columbia, Attorney General Clark and the coalition ask the Court to review EPA's new rule because it is contrary to law and EPA fails to justify its change in position.

"Climate impacts do not stop at Vermont's borders," said Attorney General Clark. "Vermont has its own rule limiting HFCs, but this rule will allow continued use of these refrigerants in other states. If it is not stopped, EPA's rule will result in further emissions of this potent greenhouse gas and contribute to climate change."

HFCs are widely used in commercial, residential, and mobile cooling systems, such as air conditioning and refrigeration. Once deemed a safer alternative for the environment relative to ozone-depleting substances (chlorofluorocarbons, or CFCs), which damage the earth's ozone layer, HFCs were later discovered to pose a major threat to the climate. With greenhouse effects hundreds to thousands of times higher than carbon dioxide over a hundred-year period, HFCs have been projected to contribute up to 0.5 degrees Celsius (about 0.9 degrees Fahrenheit) to global surface warming by 2100 if they are not controlled.

If allowed to move forward, the rule will increase HFC emissions, accelerating the damage already threatening our planet from climate change. Vermont has experienced catastrophic floods, severe storm events, and had significant air quality impacts from wildfire smoke resulting from global warming. Further, by undermining the parallel reduction in HFC supply and demand, the rule threatens to cause shortages and price spikes in the HFC market that could be passed from retailers to consumers.

In the lawsuit, Attorney General Clark and the coalition allege that EPA's final rule is arbitrary and capricious and violates the American Innovation and Manufacturing Act (AIM Act) of 2020.

Vermont is joined in this lawsuit along with California, Colorado, Delaware, Hawai'i, Illinois, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nevada, New Jersey, New York, Oregon, Rhode Island, Washington, Wisconsin, the District of Columbia, and the City of New York.

This lawsuit is the 56th case Attorney General Clark has brought against the Trump Administration since President Trump took office in January 2025. For more information on actions taken by the Attorney General on behalf of Vermonters, visit our website.

CONTACT: Haley Sommer, Senior Advisor to the Attorney General, 802-828-3171