The Supreme Court on Monday heard arguments on whether to proceed with a case that involves Muslim Americans claiming the FBI illegally surveilled them based on their relegious beliefs, while the government alleges that allowing it to move forward would divulge information that would harm U.S. national security. 

A lower court previously dismissed the case on those grounds, but in 2019 a federal appeals court reversed that decision, saying that the judge should have been able to review the information the FBI says will be harmful if released. 

Justice Neil Gorsuch, who was appointed by President Trump, appeared to be sympathetic to the plaintiffs’ case. He said the government’s position is that “we’re entitled to use that evidence in our possession without telling you anything about it as a basis for dismissing the suit more or less as a matter of routine.”

He said the government’s claim that it doesn’t have to choose between keeping secrets and defending itself is “quite a power,” particularly “in a world in which the national security state is growing larger every day.”

A government lawyer told the Court on Monday that the case should be dismissed “because the information concerning the reasons, the subjects, the sources and methods of this foreign intelligence investigation was so central to the case.” 

The plaintiffs’ attorney, meanwhile, said the case could go forward without the secret evidence and can instead rely on public information.