Montana’s legislature has passed the nation’s most aggressive anti-science law, prohibiting state agencies from considering the impacts of excess heat-trapping pollution when reviewing permits for large projects like coal mines and power plants.

Governor Greg Gianforte signed House Bill 971 into law, dealing a blow to evidence-based environmental policy, according to Inside Climate News.

This legislation comes at a pivotal time, as Montana’s climate has already changed significantly over the past century.