In 2015, when a group of 21 children and teens first sued the US government over climate change, their claim in Juliana v. US was not totally new—youth in Uganda and the Netherlands had filed somewhat similar environmental suits—but it seemed a little strange. Shouldn’t these kids be playing video games or something, doing pretty much anything but litigating to save the planet?

Now, the plaintiffs in Juliana v. US are part of an increasingly vocal global movement of young environmental activists leading the fight against climate catastrophe, most visible among them Swedish teen Greta Thunberg, who has chided world leaders for failing to take action. And they are banding together. In March, Thunberg inspired a worldwide protest, with kids skipping school to make the point that their future is on the line because of climate change. On June 1, youth activists will host nearly 100 coordinated press conferences across the US and worldwide announcing new local actions to fight the climate crisis in a show of solidarity with the American plaintiffs who have a hearing before the US Court of Appeals for the Ninth Circuit on June 4.

The young Americans, some of whom are now adults, argue that they have a constitutional right to a stable climate that sustains life on Earth. While this right is obviously not enumerated in the US Constitution, they say that it is implied by the document. By adopting policies that promote fossil fuel use, leading to the emission of carbon dioxide at rates that change the climate, despite knowing these energy sources are warming the planet, the federal government violates “the youngest generation’s constitutional rights to life, liberty, and property,” they wrote in their 2015 complaint (pdf). The plaintiffs also contend that the government is failing to protect essential resources held in trust for the public.

Their case—which originated in Oregon district court—has been surprisingly successful so far, though the government has fought the kids hard. The matter has survived efforts to dismiss it by two presidential administrations, that of Barack Obama and now of Donald Trump. The fossil fuel industry briefly intervened in the case, joining the government as defendants before asking the courts to release them from the matter, a motion which was granted in 2017. The case was set for trial twice in 2018, but the Trump administration repeatedly moved for delay and dismissal.

The kids have used social media to get out their message, naturally. When their trial was delayed in February 2017, for example, they posted using the hashtag #RatherBeInCourt.

Last July, the US Supreme Court unanimously ruled in favor of the plaintiffs, denying the administration’s application for a stay and calling a request to review the case before the district court hears all of the facts at trial “premature.” The high court again denied a Trump administration request for a stay in November. But the feds fought on and the Department of Justice immediately filed more motions to quash the case at the district and circuit court level. The government has gone to great lengths to avoid a trial that will no doubt highlight the science behind climate change and reveal the extent to which representatives failed to act on information about environmental dangers.

The hearing next week before the appeals court will determine whether the plaintiffs can finally take the case to trial and, if so, whether various federal agencies will be subject to an injunction while the trial takes place, halting the production of new fossil fuel extractions while the matter is heard. If they succeed, these young plaintiffs will be setting a dramatic precedent in the US. As they say on their website, ”Like Brown v. Board of Education did for civil rights, Juliana v. United States has the potential to become the landmark climate change case of our country’s history.”

This bold claim has merit. If the kids succeed in the US, they create a basis for other cases like theirs in municipalities and states across the nation. Though the litigation is complicated, Juliana v. US has already gone much further than the US government would have liked. A win would mean that American states and municipalities would have to rethink their obligations as trustees of public resources or risk facing similarly complex litigation, and it could change the way business is done.

Certainly, the plaintiffs have convinced many that their case matters. Ahead of the June 4 hearing, environmental groups, businesses, members of Congress, the League of Women Voters, public health experts, history professors, and of course lawyers all argued the validity of their claims in amicus briefs (32,340 young people (pdf) were also represented in such a brief). A filing on behalf of law professors (pdf) supporting the plaintiffs argues that the constitutional claim in the case is indeed valid. They write, “The District Court was correct to find that a stable climate is essential to ordered liberty…Indeed, as the District Court found, a stable climate system is quite literally the foundation of society, without which there would be neither civilization nor progress.”