Blue state attorneys general and big city governments, including Columbus and Cleveland, are suing the Trump administration over the U.S. Environmental Protection Agency’s repeal of the 2009 endangerment finding, the Obama-era legal basis for most federal greenhouse-gas rules.

Ohio was not among the states that joined the case. The repeal could erase greenhouse gas standards for cars and trucks and trigger broader changes affecting power plants and other stationary sources, putting a major piece of federal climate policy back in dispute.

The lawsuit, led by attorneys general in states such as New York, Massachusetts, California and Connecticut, all but guarantees more legal and regulatory whiplash. Politicians are again asking courts to keep Washington at the center of decisions that shape energy costs, capital planning and long-term investment.

“This is what happens when national environmental policy gets dragged back into partisan trench warfare,” said James Lee, OMA managing director of public policy services. “Instead of clarity, employers get more uncertainty, more delay and one more reminder that major business decisions can still be thrown off course by political lawsuits.”

Join OMA on Thursday, April 9, for the first Environment Committee meeting of the year and get a clear read on the environmental policy changes that could reshape compliance for Ohio manufacturers. A key part of the program will be former EPA Director Chris Jones of Calfee, Halter & Griswold, who will break down what changes to the 2009 Endangerment Finding and evolving greenhouse gas reporting rules could mean for your operations. 3/23/2026