The US Supreme Court on Monday heard two hours of arguments in a case involving three Muslim men in California who claim they were surveilled at their mosque by the FBI following the September 11 attacks.
The three men — Yassir Fazaga, imam of the Orange County Islamic Foundation, as well as Ali Uddin Malik and Yasser Abdelrahim — say the FBI sent a confidential informant to several mosques in the county in 2006 and 2007.
The head of the FBI office in Los Angeles, Stephen Tidwell, held a town hall at the California mosque in 2006 where he repeatedly assured the audience they were not being monitored, all while actively recruiting an informant, NPR reported.
Justices on Monday struggled over whether to allow the lawsuit to go forward despite the government's objection that doing so could reveal state secrets - such as whom the government was investigating and why.
Some justices suggested they were inclined to agree with the government but also seemed to favour sending the case back to a lower court for additional proceedings.
The US Justice Department has maintained that it launched the surveillance programme for objective reasons — not because those being watched were Muslims.
A lower court dismissed almost all their claims after the government said allowing the case to go forward could reveal state secrets.
But an appeals court reversed that decision, saying the lower court first should have privately examined the government's evidence to see if the surveillance was unlawful.
The Supreme Court will decide whether a district court can consider classified evidence in determining whether secret government surveillance is lawful.
The case is “tremendously important”, said Ahilan Arulanantham - a lawyer with the American Civil Liberties Union who is representing the plaintiffs before the Supreme Court - because it goes to the question of whether the government can simply invoke state secrets to quash any challenge to its surveillance programmes, even in the face of “very serious claims, well supported by declarations, of religious discrimination".
The Supreme Court is expected to render its decision in the case of Federal Bureau of Investigation v Fazaga by June 2022.
At the time, the informant, Craig Monteilh, a local gym trainer with a criminal record, was instructed by the FBI to infiltrate the Islamic Centre of Irvine.
The informant “told everybody that he was a convert, that he was wanting to rediscover his French-Algerian roots”, said Mr Arulanantham.
“He then was instructed by the FBI to gather as much information as possible on people in this community — cell phones, email addresses, conversations, which he secretly recorded,” Mr Arulanantham told reporters.
The ACLU says the informant recorded prayer groups at the mosque with a device hidden in his car key fob and that he also recorded videos in mosques, homes and businesses.
As they were being peppered with questions on violence, Mr Monteilh's new acquaintances grew uneasy.
“I said we should carry out a terrorist attack in this country,” the informant told documentarian Sam Black on This American Life.
“We should bomb something.”
Members of the community reported him to the FBI and other authorities, and sought a restraining order against him.
The FBI acknowledged Mr Monteilh was an informant.
The imam and his two congregants filed a complaint against the FBI for spying on them in breach of federal law and their constitutional rights, claiming they were spied on solely because of their faith.
“We believe that we were targeted not because of anything other than our religious beliefs,” Mr Fazaga told NPR.
The informant tried to persuade the congregants “to become terrorists”, he said.
Agencies contributed to this report