In a 6-1 ruling yesterday, Montana’s Supreme Court upheld a landmark decision finding that a 2011 state law making it illegal to consider environmental impacts (including greenhouse gas emissions) when issuing permits for fossil fuel development violated plaintiffs' constitutional right to a clean and healthful environment.

In making their argument, the 16 youth activist plaintiffs cited a 50-year-old constitutional clause that guaranteed the “state and each person shall maintain and improve a clean and healthful environment in Montana for present and future generations.” 

The state's governor criticized the ruling in a statement, arguing that the decision will lead to “perpetual lawsuits” that will “waste taxpayer dollars and drive-up energy bills” for Montanans. He also accused the court of making policy outside of its purview.

Similar climate lawsuits are ongoing across the United States, but this is the first ruling from a state supreme court on this issue.