On March 19, 2026, Massachusetts Attorney General Andrea Campbell led a coalition of 24 states, the District of Columbia, the U.S. Virgin Islands, and 12 cities and counties in filing a lawsuit challenging the Environmental Protection Agency’s (EPA) unlawful attempt to rescind its 2009 Endangerment Finding, which determined that greenhouse gas emissions from motor vehicles contribute to air pollution that drives climate change and endangers public health and welfare. The Endangerment Finding has served as the basis for all government action to combat climate change and supports restricting emissions under the Clean Air Act.  

The Endangerment Finding was a result of a 2007 Supreme Court case that confirmed that Congress authorized the EPA to regulate greenhouse gases under the Clean Air Act. The finding was based on years of rigorous scientific study and review. In repealing the finding, the Trump administration ignores both the Supreme Court’s decision and reasoning, and disregards decades of peer-reviewed science demonstrating the severity of climate change and the direct harms caused by greenhouse gas emissions.   

The long-term harms of greenhouse gases cannot be understated. Average temperature increases have led to thousands of heat-related deaths each year across the country, in addition to straining electrical grids and other infrastructure. Increased storm intensity and rising sea levels cause billions of dollars in damages. And degraded air quality exacerbates public health issues such as asthma and other respiratory illnesses. 

By rescinding the endangerment this finding, the EPA has eliminated the basis for many federal climate protections, including vehicle emissions standards and investments in clean energy. The coalition has challenged the new agency action, arguing that the rollback is unlawful because it is contrary to the agency’s responsibilities under the Clean Air Act, it ignores scientific findings, and represents a preordained conclusion. 

By rescinding the Endangerment Finding, the EPA is stripping away protections that have shielded Marylanders from rising floods, extreme heat, and toxic air since 2009. We’re filing this lawsuit to stop a dangerous future driven by a decision that puts polluters over people.Attorney General Anthony Brown

The administration’s actions continue to ignore the real consequences of climate change for Washingtonians: increased air pollution, more frequent flooding, rising storm surges on the coasts, reduced snowpack in the mountains, and the destruction and smoke impacts of increasing wildfires throughout the state. Washington is leading the nation in addressing climate change, but the federal government has an obligation to acknowledge what’s driving it and to protect people from pollution.Attorney General Nick Brown

Climate change is real, and it’s already affecting our residents and our economy. When the federal government abandons the law and the science, everyday people suffer the consequences. As a mom, I want my boys – and every child in our state – to grow up breathing clean air and playing safely outdoors. Massachusetts has long led the way in protecting our communities from the dangers of greenhouse gas emissions and we are proud to stand up once again to lead this fight for our future.Attorney General Andrea Campbell