MICA KANTOR IS a long-distance runner. At 15 years old, he enjoys unplugging from his phone while he runs outdoors. But as wildfires have become more frequent in recent years, smoky days have increasingly limited his ability to train outside. That makes him “feel trapped,” he said recently in a Montana state courtroom, “like I can’t get my mind off of things.”

Sariel Sandoval, 20, a member of the Bitterroot Salish, Upper Pend d’Oreille, and Diné tribes, grew up picking huckleberries with her family and listening to coyote stories. Some tales, which have been passed down through generations, are told only when there is snow on the ground. “One day we’re not going to have any snow on the ground,” she testified in court. “What happens to those stories?”

Olivia Vesovich, a 20-year-old artist, says her allergies have become more and more painful in recent years, even swelling her eyes shut at times. On top of that, wildfire smoke has been triggering her asthma. “I feel like I can’t breathe, and that’s a terrifying feeling,” she said.

Kantor, Sandoval, and Vesovich are among a group of 16 young people, ages 5 to 22, who sued Montana in 2020 for contributing to the climate crisis. All three took to the witness stand this summer in Held v. Montana, laying bare, in sometimes emotional testimony, the ways in which climate change has impacted their physical, mental, and cultural health. In August, the district court judge ruled in their favor in a landmark win for the climate movement.

The lawsuit was highly anticipated in climate circles. It was the first youth-led climate case to go to trial in the United States. It was also the first constitutional climate case to go to trial in the country, meaning the legal argument for this case rested on inalienable rights bestowed to all Montanans in the state constitution.

“There’s never been a trial like this in our history.”

“There’s never been a trial like this in our history,” said one of the lead attorneys in the case, Nate Bellinger, of Our Children’s Trust, the nonprofit law firm representing the plaintiffs. There are, however, sure to be more: Youth plaintiffs across the country are gearing up to fight for their climate rights in several other cases.

What sets the Held case apart, though, is that it is centered around a relatively unique constitutional protection: A so-called “green amendment” that guarantees the right “to a clean and healthful environment in Montana for present and future generations.” In tandem with a recent rise in climate cases, there is a growing movement to pass green amendments like this in other states around the country. If successful, some experts say this parallel movement would strengthen legal grounds for climate activists and could be a game changer for climate litigation in the United States.

ONE OF ONLY THREE STATES with a green amendment baked into its bill of rights, Montana embedded these protections in the state constitution in 1972, during the rise of the modern environmental movement. Pennsylvania passed a similar green amendment protecting the “right to clean air, pure water, and to the preservation of the natural, scenic, historic and esthetic values of the environment” in 1971. New York passed its own green amendment just two years ago.

The young plaintiffs in Held argued that their right to a clean environment fundamentally includes the right to a stable climate system, and that by supporting fossil fuel development in Montana, the state is violating that right. In other words, it targets the “government role in allowing fossil fuels and [argues] that the injuries and harms that result from those fossil fuel activities are violating the constitutional rights of the plaintiffs in Montana,” Bellinger said.

The victory in Held reinforces the power of green amendments in the climate context, a power that Maya van Rossum thinks could offer a major check on bad behavior by state actors, one not offered under environmental legislation. “I really do believe that this is the transformational underpinning that we need to really make progress moving forward,” she said.

Van Rossum’s on a mission to make that transformation happen. As an attorney and founder of the nonprofit Green Amendments for the Generations, she is dedicated to embedding a self-executing right to a clean environment in the bill of rights of every state constitution across the nation, and ultimately in the federal Constitution, too. Such rights do not require legislation to be enforceable.

Her definition of a green amendment is narrow: The right to a healthy environment has to be included in a state’s bill of rights, which puts it on par with most fundamental constitutional rights, such as free speech or religious liberty. While a handful of other states — including Illinois, Massachusetts, and Hawai‘i — have some type of constitutional protections to a clean environment, so far only Montana, Pennsylvania, and New York have met this standard.

This year, nine states have introduced green amendment legislation, and six more are considering similar efforts.

To van Rossum, it’s an essential distinction. “There are a lot of states that talk about the environment, talk about environmental protection, even talk about environmental rights in their constitutions. But they do it in a way that does not give the same strength, or power, or quality that a green amendment does.”

Though the movement has faced pushback from industry, including from large-scale renewable energy developers, it’s gaining momentum. This year alone, nine states introduced green amendment legislation, and six more are considering similar efforts. Many of these proposed amendments — which have cropped up in states including New Mexico, Texas, and Hawai‘i — include an explicit right to a stable climate alongside the right to clean air and water, something the existing green amendments lack. Ideally, van Rossum said, they would also include language ensuring the rights of future generations, as the Montana constitution does.

Van Rossum’s faith in the power of green amendments traces back to 2012. That year, the Pennsylvania legislature passed a law that pre-empted the ability of local municipalities to ban drilling and fracking in their jurisdictions. Fracking posed a major threat to the Delaware River watershed, so van Rossum, who is the Delaware Riverkeeper, and seven municipalities decided to take Pennsylvania to court. They based their case in part on the state’s green amendment, which she says hadn’t fared particularly well in the courtroom up to that point. But in a major — and unexpected — decision, Pennsylvania’s Supreme Court sided with the Delaware Riverkeeper and its co-plaintiffs, finding that the state had violated Pennsylvanians’ fundamental right to a clean environment.

Since then, the green amendments of Pennsylvania and Montana have played key roles in cases challenging water quality, toxic contamination, and air pollution. Or, as Michael Gerrard, the founder and faculty director of Colombia Law School’s Sabin Center for Climate Change Law, put it, after a long period of dormancy, “the significance of these amendments is now emerging full force.”

Gerrard thinks the movement for green amendments could make a big difference to environmental litigators. “If it’s successful, it could be very consequential,” he said.

While green amendments are gaining traction at the state level, the federal level is a different story. Passing amendments to the US Constitution is much more difficult.

“A justice can try to manipulate and nibble around the edges, ... but they cannot wholesale throw out what ... the constitutional entitlement is.”

Still, van Rossum is hopeful that the state-level movement will lay the foundation to, “at some point in the near future, be able to start to work towards a federal green amendment and really have a shot at getting it.”

Were we ever to get a federal constitutional right to a clean environment, van Rossum thinks it would be difficult even for today’s conservative US Supreme Court to ignore. “When you have very clear constitutional language, with that bill of rights placement,” she said, “a justice can try to manipulate and nibble around the edges, … but they cannot wholesale throw out what the language is and what the constitutional entitlement is.”

Bellinger, the attorney in the Held case, is careful to mention that green amendments aren’t essential to climate rights lawsuits. The case he and his colleagues laid out in Held makes this point. The state’s green amendment provided a strong claim, to be sure, but other successful claims asserted violations of the youths’ right to equal protection under the law, and their right to seek safety, health, and happiness.

“I think these are rights that people already have,” he said of environmental rights, whether or not they are explicitly laid out. “I wouldn’t want people to think that if you tried to amend the constitution in a certain state to add the right to a healthful environment, and it didn’t pass for some reason, that you therefore didn’t have those rights.”

WHILE HELD WAS the first constitutional climate case in the United States, it is not the first globally. The number of climate cases around the world has doubled over the past five years. A growing share of recent cases involve rights-based arguments, many resting on constitutional rights, including successful cases in Colombia, Nepal, and Pakistan. (Globally, 149 countries explicitly mention environmental rights in their national constitutions, though they vary in substance and strength. The US is not among them.)

“We’re seeing … real growth in climate change litigation around the world, including notable successes in several countries,” Gerrard said. “Environmental constitutional provisions have often played an important role in the successful decisions.”

That growth is reflected in the US as well: There are currently more than 1,500 climate cases of various sorts underway, more than half of all cases globally. Key among them are a youth-led case to be heard next year in Hawai‘i that relies in part on environmental rights provided for in the state constitution, and the much-anticipated youth-led case against the federal government, Juliana v. United States, which argues that the government’s contribution to climate change violates youths’ right to life and liberty under the US constitution. In June, Juliana received a judicial greenlight to head to trial. Plaintiffs in both cases are represented by Our Children’s Trust.

“The climate keeps on getting worse and worse,” Gerrard said. “And most governments continue to do not nearly enough ... In the absence of adequate action, more and more people are going to resort to the courts.”

In that context, the decision in Held — which requires Montana now consider climate impacts when considering new fossil fuel projects — holds special weight. As the first US constitutional climate trial, “it is really important precedent that will obviously be binding in Montana, and I think persuasive precedent in other states and actually other countries,” Bellinger said.

The Montana decision — delivered just after the hottest July on record — couldn’t have come soon enough. From historic flooding in Vermont, to apocalyptic smoke in New York, to the deadly August wildfires on Maui that killed more than 100 people, the catastrophic effects of climate change were on clear display across the country this summer. Montana wasn’t exempt: Parts of the state experienced extreme heat, smoky skies, and severe drought as the 16 young people awaited the ruling.

“It’s really scary seeing what you care for disappear right before your eyes,” Sandoval said during the trial, her eyes tearing up and her voice cracking as she explained why she joined the case. “And I thought what this case was doing, and what you guys are doing, is really important … And I’m very grateful I have a voice here. But a lot needs to be done. This is only one step.”

One step, yes, but a successful one, and one step closer to climate accountability for our governments.