WHETHER a constitutional right to a healthy, livable climate is protected by state law is at the centre of a lawsuit going to trial on Monday in Montana in the United States.

Sixteen young plaintiffs hope to set an important legal precedent to establish a government duty to protect citizens from climate change.

The trial comes shortly after the state’s Republican-dominated legislature passed measures favouring the fossil fuel industry by stifling local government efforts to encourage renewable energy while increasing the cost to challenge oil, gas and coal projects in court.

By enlisting plaintiffs ranging in age from 5 to 22, the environmental firm bringing the lawsuit is trying to highlight how young people are harmed by climate change now and will be further affected in the future. 

Their testimony will detail how wildfire smoke, heat and drought have harmed residents’ physical and mental health.

The plaintiffs’ youth has little direct bearing on the legal issues, and experts say the case likely won’t lead to immediate policy changes in fossil fuel-friendly Montana.

But during what is likely to be about two weeks of testimony, attorneys for the plaintiffs plan to call out state officials for pursuing oil, gas and coal development and send a powerful message to other states.

Plaintiff Grace Gibson-Snyder said she has felt the impacts of the heating planet acutely as wildfires regularly shroud her hometown of Missoula in dangerous smoke and as water levels drop in area rivers.

She said the state legislature was repeatedly choosing corporations over the needs of their citizens.

Other young plaintiffs include members of Native American tribes, a ranching family dependent on reliable water supplies and people with health conditions such as asthma that put them at increased risk during wildfires.

Lawyers for Montana Attorney General Austin Knudsen, a Republican, tried repeatedly to get the case thrown out over procedural issues. 

In a June 6 ruling, the state supreme court rejected the latest attempt to dismiss it, saying justices were not inclined to intervene just days before the start of a trial that has been “literally years in the making.”

The case was brought in 2020 by attorneys for the environmental group Our Children’s Trust, which has filed climate lawsuits in every state on behalf of young plaintiffs since 2011. 

Trust founder Julia Olson said: “It will change the future of the planet if courts will start declaring the conduct of government unconstitutional.”