U.S. Supreme Court Decides to Hear Climate Case Against ExxonMobil and Suncor Entities

Kevin Hannon, Partner at Singleton Schreiber, was featured by Boulder County in an article titled “U.S. Supreme Court Decides to Hear Climate Case Against ExxonMobil and Suncor Entities,” published on February 23, 2026.

Hannon represents Boulder County and the City of Boulder in their climate accountability litigation against Exxon Mobil and Suncor entities. The case seeks to hold the companies accountable under Colorado law for alleged in-state harms related to climate change. Hannon’s role includes advancing the plaintiffs’ position that the claims properly proceed in state court.

The legal issue before the U.S. Supreme Court concerns whether federal law preempts state law claims seeking damages for local climate-related harms. The Court will consider the companies’ argument that federal law shields them from state-level accountability, following a Colorado Supreme Court ruling allowing the case to proceed.

“The Colorado Supreme Court properly ruled that Colorado law is fully capable and appropriate to address climate harms occurring in Colorado. After over seven years, Boulder County and the City of Boulder should be permitted to have their day in court,” said Kevin Hannon, Partner, Singleton Schreiber, LLP.