PORTLAND, Ore. (AP) — The U.S. Supreme Court on Monday declined to hear a petition filed by young climate activists who argued that the federal government's role in climate change violated their constitutional rights, ending a decadelong legal battle that saw many of the plaintiffs grow from child ren and teenagers into adults. The landmark case was filed in 2015 by 21 plaintiffs, the youngest 8 years old. They claimed the U.S. government's actions encouraging a fossil fuel economy violated their right to a life-sustaining climate. The case — called Juliana v. United States after one of the activists, Kelsey Juliana — was challenged repeatedly by the Obama, Trump and Biden administrations, whose lawyers argued it sought to direct federal environmental and energy policies through the courts instead of the political process. Julia Olson, chief legal counsel for Our Children's Trust, the nonprofit law firm that represented the plaintiffs, said the impact of the lawsuit “cannot be measured by the finality of this case alone.” “Juliana sparked a global youth-led movement for climate rights that continues to grow," Olson said in a statement Monday. “It has empowered young people to demand their constitutional right to a safe climate and future. We’ve already secured important victories, and we will continue pushing forward.” What happened with the case? The plaintiffs wanted the court to hold a trial on whether the U.S. government was violating their fundamental rights to life and liberty by operating a fossil-fuel based energy system. The case wound its way through the legal system for years. At one point in 2018, a trial was halted by U.S. Supreme Court Chief Justice John Roberts just days before it was to begin. In 2020, the 9th U.S. Circuit Court of Appeals ordered the case dismissed, saying the job of determining the nation’s climate policies should fall to politicians, not judges. But U.S. District Judge Ann Aiken in Eugene, Oregon, instead allowed the activists to amend their lawsuit and ruled the case could go to trial. Last year, acting on a request from the Biden administration, a three-judge 9th Circuit panel issued an order requiring Aiken to dismiss the case, and she did. The plaintiffs then sought, unsuccessfully, to revive the lawsuit through their petition to the U.S. Supreme Court. Our Children's Trust, responding to new developments at the federal level, is now preparing a new federal action that is “rooted in the same constitutional principles that guided the Juliana case," Olson said. Who are the plaintiffs? The plaintiffs now range from 17 to 29 years old and have continued their climate advocacy to various degrees, Olson said, adding that some are still in university. About half are from hometowns in Oregon, according to Our Children's Trust's website. “They all have incredible stories,” Olson said. “They're all doing incredible work.” Juliana, who is now 29, became a primary school teacher in Oregon, said Helen Britto, associate communications director for Our Children's Trust. Other plaintiffs include Alex Loznak, who became a lawyer focused on environmental and immigration work, and Nathan Baring, who now serves as the program director of a reindeer herding association in Alaska. “We’re part of a wave, so this is not the end of the road by any means,” Baring said of the high court's move. Miko Vergun, who was born in the Marshall Islands and grew up in Beaverton, Oregon, is fighting for a future where the Pacific island nation can stay above sea level, according to Our Children's Trust's website. She recently graduated from Oregon State University with a degree in cultural anthropology, Britto said. In Monday's statement, Vergun said the U.S. Supreme Court decision wasn’t what the plaintiffs had hoped for, but there had been “many wins along the way.” “For almost ten years, we’ve stood up for the rights of present and future generations, demanding a world where we cannot only survive, but thrive," she said. "All great movements have faced obstacles, but what sets them apart is the perseverance of the people behind them. We’ve shown the world that young people will not be ignored, and I’m incredibly proud of the impact Juliana v. United States has made.” What about other youth climate lawsuits? Our Children's Trust has filed climate legal actions on behalf of young people in all 50 states, including active cases in Florida, Utah and Alaska. In a Montana case, the state Supreme Court in December upheld a landmark climate ruling that said the state was violating residents’ constitutional right to a clean environment by permitting oil, gas and coal projects without regard for global warming, and that regulators must consider the effects of greenhouse gas emissions when issuing permits for fossil fuel development. The case, brought by 16 youth plaintiffs, had gone to trial in state district court in 2023. The Montana Constitution requires agencies to “maintain and improve” a clean environment. The Montana Department of Environmental Quality, which issues permits for fossil fuel projects, has to abide by the state Supreme Court decision, Olson said, adding that Our Children's Trust will seek to enforce the ruling in the event it is violated. In a Hawaii case brought by 13 youth over the threat of climate change, both sides reached a settlement last year that requires the state government to achieve zero emissions in its transportation system by 2045. The settlement agreement applies to ground transportation, as well as sea and air transportation between islands. The court will supervise the implementation of the agreement for the next 20 years. Internationally, the Oregon case has inspired over 60 youth-led climate lawsuits across the world, according to Our Children's Trust. ...read more read less