SAN FRANCISCO—At least two members of a Ninth Circuit panel appeared unlikely to allow an interim appeal to stamp out a lawsuit claiming a constitutional right to be secure from the effects of climate change.

Both Ninth Circuit Chief Judge Sidney Thomas and Judge Marsha Berzon indicated at oral argument Monday that granting the government's unusual mandamus petition in the case could open the floodgates to other litigants who lose out on motions to dismiss.

Government lawyers have argued that a federal judge in Oregon erred last year when she found that plaintiffs in the case—including a group of 21 young people seeking further federal actions to curb climate change—have an “unenumerated fundamental right” to “a climate system capable of sustaining human life.”

DOJ lawyers in both the Obama and Trump administrations have argued that plaintiffs don't have standing to sue, and that there's no due process right to a livable climate.

But on Monday, Berzon told Deputy Assistant Attorney General Eric Grant that the government could appeal once it had something of substance from the court below to appeal and seemed to indicate that she'd be a vote in favor of letting the litigation below run its course. If the Ninth Circuit stepped in too soon, she said the appellate court would be faced with “hundreds” more cases every day asking to review lower court decisions denying motions to dismiss.

Thomas agreed, adding: “We'd be flooded with appeals from people who think their case should have been dismissed by the district court.”

But the lawyer for the plaintiffs, Julia Olson of Wild Earth Advocates, faced pointed questions from the third judge on the panel, Circuit Judge Alex Kozinski, sitting for his first oral argument after the Washington Post reported Dec. 8 that six women said he asked them to view pornography or subjected them to inappropriate comments.

When Olson said she had found no other case where a court of appeals had granted mandamus on standing, Kozinski said that there was “much unprecedented about this case.”

“It may suggest we need to take unprecedented action.”

Later in the argument, Kozinski questioned whether the plaintiffs' young age made them more likely to have standing to sue than any other citizen bringing climate change-related claims against the government. Olson then cited one of Kozinski's own dissents in a case dealing with the foster care system that said “the brunt of the state's policy falls on the children who, after all, have no say in the matter.”

“Quirky,” said Kozinski of his own writing, before noting that the case Olson cited dealt with issues specific to children, where the case at hand has broader issues at play. “Whatever harm they're suffering is the same as everybody else in the country,” Kozinksi said.

After the arguments, Olson and co-counsel Philip Gregory at Cotchett, Pitre & McCarthy crossed the street from the courthouse to a crowd of supporters. The group chanted and sang surrounded by banners and signs reading “Let the Youth be Heard” and “#youthvgov.”

Olson told the crowd that it's time for courts to act as “bulwarks” for citizens against abuses of power.