A Montana law promoting fossil fuels violated the state’s constitutional guarantee of a “clean and healthful environment,” a state judge ruled Monday. The case was brought by nonprofit law firm Our Children’s Trust along with the Western Environmental Law Center and McGarvey Law on behalf of 16 young Montanans, ages 5 to 22.

The sweeping order in Held v. Montana, which includes extensive findings on the science of climate change, found provisions of the Montana Environmental Policy Act (MEPA) prohibiting the state from considering greenhouse gas pollution in environmental reviews of energy projects violated the plaintiffs’ rights because the state’s greenhouse gas pollution is “nationally and globally significant,” and as such “cause and contribute to climate change and plaintiffs’ injuries and reduce the opportunity to alleviate Plaintiffs’ injuries.”

“I’m so speechless right now,” Eva, a plaintiff who was 14 when the suit was filed, said in a statement. “I’m really just excited and elated and thrilled.”

“This is a huge win for Montana, for youth, for democracy, and for our climate,” Our Children’s Trust founder Julia Olson said. “More rulings like this will certainly come.” The state has 60 days to appeal the ruling to the Montana Supreme Court.

Michael Gerrard, founder of Columbia’s Sabin Center for Climate Change Law, also praised the ruling. “I think this is the strongest decision on climate change ever issued by any court,” he told The Guardian. (The Guardian, AP, Washington Post $, The Hill, New York Times $, Gizmodo, Reuters, CNN, Axios, Politico, Bloomberg $, Vox)