Montana top court upholds landmark youth climate ruling

Montana's Supreme Court has upheld a lower court's decision that had sided with 16 young activists who argued that the state violated their right to a clean environment.

The lawsuit was brought by students arguing that a state law banning the consideration of climate when choosing energy policy was unconstitutional.

In a 6-to-1 ruling, the top court found that the plaintiffs, between ages five and 22, had a "fundamental constitutional right to a clean and healthful environment".

Wednesday's ruling came after a district court's decision last year was appealed by the state. Similar climate lawsuits are ongoing across the US but this is first of its kind a from a state supreme court.

The lawsuit targeted a 2011 state law that made it illegal for environmental reviews to consider climate impacts when deciding on new projects, like building new power plants.

It 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 ruling on Wednesday stated that the "plaintiffs showed at trial - without dispute - that climate change is harming Montana's environmental life support system now and with increasing severity for the foreseeable future" .

Rikki Held, the lead plaintiff in the lawsuit, said in a statement that "this ruling is a victory not just for us, but for every young person whose future is threatened by climate change".

Montana state officials expressed disappointment with the court's decision.

Governor Greg Gianforte said his office was still assessing the ruling, but predicted the impact would be "perpetual lawsuits that will waste taxpayer dollars and drive up energy bills for hardworking Montanans".

Western Environmental Law Center, which represented the young plaintiffs, said in a statement that the decision marks "a turning point in Montana's energy policy".

It said plaintiffs and their legal team "are committed to ensuring the full implementation of the ruling".

Similar cases are scheduled to be heard in several other states, including Hawaii, Utah and Alaska, as well as in countries like Australia, New Zealand, Pakistan, Colombia and Uganda.