Hailed as the first major climate trial victory in the United States, the Montana First Judicial District Court in Held v. State of Montana, 2023 WL 5229257 (Mont. Dist., 2023), declared that Montana's energy policy unconstitutionally promotes the development and utilization of fossil fuels, and deemed unconstitutional the Montana Environmental Policy Act (MEPA) prohibiting the state from considering the impacts of climate change when making certain permitting decisions thereby preventing courts and agencies from considering a project's climate impacts.

The court found a clear causal link between authorizing the projects under agency review, their direct contributions to global greenhouse gas (GHG) emissions, and the harm to children already living with these impacts "because of their unique vulnerabilities, their stages of development as youth, and their average longevity on the on the planet in the future" creating "lifelong hardships resulting from climate change."

The Montana Attorney General's Office criticized the decision as "a week-long taxpayer publicity stunt" and quipped that "Montanans can't be blamed for changing the climate." Nonetheless, Held has broad standing and evidentiary implications for litigants in states like New York now benefiting from constitutionally ingrained environmental rights.