As the Earth grows hotter, young people facing decades of environmental disruption have turned to the courts for relief. A group of teenagers has sued the U.S. government because it hasn’t done enough to protect future generations from climate change. The novel case has made it further than many legal observers thought possible and is getting close to trial. If the teens prevail, the government could be forced to create a plan to cut greenhouse gases more extensively than anything it’s done before.

1. What grounds are there for a lawsuit?

The group says the U.S. government has violated their constitutional right to a livable climate by not keeping greenhouse gas emissions at a level needed to contain global warming. They also argue the atmosphere is part of the public trust that the government must maintain for its citizens.

2. What makes it novel?

If the court rules in favor of the kids’ constitutional claims, it would acknowledge a new climate-based fundamental right. Supporters of the lawsuit sometimes compare those claims to Obergefell v. Hodges, the landmark 2015 case in which the Supreme Court recognized the fundamental right to marry extended to same-sex couples. Climate lawsuits using the public trust doctrine have become more common, although they haven’t had much success to date in the U.S.

3. What is ‘public trust’?

Under the public trust doctrine, the government holds essential natural resources, such as land, water, and wildlife, in trust for its citizens. Climate litigators, including the kids in this case, argue that should include the atmosphere.

4. Who are these young people?

A group of 21 plaintiffs, now ranging in age from 11 to 22, brought the lawsuit in 2015 against the administration of President Barack Obama. Many of the kids were involved in state-level climate cases and activism before bringing the federal suit. One plaintiff is the granddaughter of well-known climate scientist James Hansen. The group has the backing of Our Children’s Trust, which has brought a number of similar U.S. climate lawsuits at the state level and supported litigation in Asia, Africa and Europe.

5. How has the U.S. government responded?

The Obama administration tried to get the case dismissed, but it had climate policies to stand behind as a defense. Before Obama left office, the administration submitted a response to the court agreeing with much of the climate science information put forth by the kids. President Donald Trump’s administration, which inherited the suit, has also tried to keep it from heading to trial. The administration argues the case would violate separation of powers by allowing the courts to dictate climate policy, which it says is squarely in the purview of the executive branch.

6. How have judges ruled so far?

Oregon district judge Ann Aiken repeatedly has denied the government’s request to dismiss the case, ruling the question of a constitutional right to a healthy environment deserves an answer. Both the U.S. Court of Appeals for the Ninth Circuit in San Francisco and the U.S. Supreme Court have rejected attempts to kill the case before trial. When the Supreme Court deferred to the Ninth Circuit in November, it ruled the courts must consider the merits of the claims to determine if a trial is warranted. An opinion from the Ninth Circuit is forthcoming. Judge Aiken said she’s prepared to promptly schedule a trial date once the Ninth Circuit lifts its hold on the suit.

7. What might happen at a trial?

The government could find itself on the spot to counter the scientific consensus about climate change. In May, Ken Caldeira, an atmospheric scientist at the Carnegie Institution for Science, turned down an opportunity to lead a team of researchers to testify on behalf of the government. And the government’s own scientists may not get on board. Thirteen federal agencies released a report in November showing climate change could cost the U.S. billions and threaten Americans’ health.

8. What happens if the government loses?

The government could have to develop a comprehensive policy to address greenhouse gas emissions across the economy. The court could set a specific emissions goal in line with the climate science presented by the kids. The plaintiffs also want a dramatic shift away from fossil fuels that could include ceasing federal leasing and support for fossil energy projects. Critics worry court-ordered climate policy could severely limit energy decisions a president might make based on economic conditions or security threats, which might test even a future administration that wants to act on climate.

To contact the reporters on this story: Abby Smith in Washington at asmith@bloombergenvironment.com;Kartikay Mehrotra in San Francisco at kmehrotra2@bloomberg.net

To contact the editors responsible for this story: Jessica Coomes at jcoomes@bloomberglaw.com Anne Cronin

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