Chicago Joins Legal Challenge Against EPA’s Greenhouse Gas Emission Rollback

The City of Chicago has joined a coalition of 24 states, the District of Columbia, the U.S. Virgin Islands, and 12 cities and counties in challenging the U.S. Environmental Protection Agency’s (EPA) decision to rescind its 2009 Endangerment Finding. This landmark finding determined that greenhouse gas emissions from motor vehicles endanger public health and welfare.

The Endangerment Finding and Its History

The 2009 Endangerment Finding stemmed from the 2007 Supreme Court case Massachusetts v. EPA, which affirmed the EPA’s authority to regulate greenhouse gas emissions under the Clean Air Act. Following the finding, the EPA established federal standards that led to reductions in motor vehicle greenhouse gas emissions.

EPA’s Rescission and the Legal Challenge

In February 2026, the EPA finalized a rule rescinding the 2009 Endangerment Finding and repealing all motor vehicle greenhouse gas emission standards. The EPA claims this action will save Americans over $1.3 trillion, but critics argue it disregards both legal precedent and scientific consensus.

The lawsuit, filed in the U.S. Court of Appeals for the District of Columbia Circuit, asserts that the EPA’s rescission violates its legal obligations and fundamental principles of administrative law. A similar suit was filed in February 2026 by public health and environmental groups.

Chicago’s Response and Commitment

Mayor Brandon Johnson stated that Chicago will fight to protect its residents, particularly Black and Brown communities, which are disproportionately vulnerable to climate change. The city previously submitted comment letters urging the EPA to abandon the proposal, arguing it would endanger millions of Americans and disrupt the regulatory landscape.

Chicago’s Law Department has been involved in over 60 legal actions against the previous administration, including 12 lawsuits and 35 amicus briefs, challenging policies related to SNAP benefits, birthright citizenship, DEI programs, and transgender rights.

Cities and States Involved

Besides Chicago, other cities participating in the lawsuit include Cleveland, Columbus, Denver, Los Angeles, New York, and San Francisco. The coalition also includes 23 attorneys general and seven counties.