Ruling sends Chicago’s Big Oil lawsuit back to state court

The latest defeat for Big Oil allows Chicago’s climate deception case to proceed toward trial.

News & Analysis

May 20, 2025

In another win for communities seeking to hold Big Oil accountable for their decades of climate lies, a federal court last week ruled that Chicago’s lawsuit against fossil fuel companies should move forward in state court, where it was first filed. U.S. District Court Judge Franklin U. Valderrama joins more than a dozen federal district court judges — and eight federal appeals courts — who have unanimously ruled against the fossil fuel industry’s arguments for moving climate accountability cases out of state court. 

Chicago’s case, first filed in 2024, charges major oil companies, including ExxonMobil, Chevron, BP, and Shell, as well as the American Petroleum Institute, with knowingly fueling the climate crisis for decades while lying to the public about the reality of climate change. The case seeks to make the oil companies pay for the damages caused by their climate deception.

“Chicago is enduring extreme heat and precipitation, flooding, sewage flows into Lake Michigan, damage to city infrastructure, and more,” said Chicago Alderman Matt Martin when the city sued last year. “That all comes with enormous costs… [W]e intend to shift those costs back where they belong: on the companies whose deceptive conduct brought us the climate crisis.” 

This week’s ruling marks an early victory for the case. Big Oil defendants have routinely tried to move climate accountability lawsuits to federal court — only to have courts and judges across the country unanimously rule in favor of sending the cases back to state court where they were originally filed. Dozens of courts have rejected Big Oil’s attempts to move the cases and the U.S. Supreme Court has declined to review the issue three times since 2023.

Now that a growing number of climate accountability cases are moving forward in state court, many judges have ruled that state and local governments can proceed toward putting Big Oil on trial based on the facts of the case. Others, however, have sided with the fossil fuel companies and those rulings are being appealed.  

“This ruling is an important victory for the people of Chicago that brings them one step closer to putting Big Oil companies on trial for their climate lies and make them pay for damage they’ve caused,” said CCI President Richard Wiles. “The people of Chicago are paying the price for climate damages that Big Oil companies knowingly fueled for years. It’s past time that these companies are held accountable for defrauding the public.”

Photo credit: Jerry Posluszny / Flickr CC BY-NC 2.0