A lawsuit against the National Security Agency’s dragnet interception of Internet communications had its first day in federal court Friday, with a diverse coalition of organizations asking a judge to rule against the Obama administration’s request that their case be dismissed.

U.S. District Judge T.S. Ellis didn’t rule from the bench or betray a clear leaning during arguments.

The case was filed in March by the Wikimedia Foundation, which operates Wikipedia, along with the National Association of Criminal Defense Lawyers, Amnesty International USA, PEN American Center, Human Rights Watch, The Nation magazine and other human rights and advocacy groups.

The groups are represented by the American Civil Liberties Union and say the NSA’s “upstream” collection of Internet communications from the cables, routers and switches that make up the Internet’s backbone is unconstitutional.

The upstream collection is – along with the PRISM program that collects communications directly from companies like Google and Facebook – a major source of Internet records the government says it’s authorized to acquire through Section 702 of the Foreign Intelligence Surveillance Act.

Ellis, seeming to enjoy vacillating between sternness and folksy charm, told ACLU attorney Patrick Toomey, “This isn’t politics, you’re not on the stump!” He warned Justice Department attorney Rodney Patton that “when I start [talking] you need to stop.”

The hearing focused largely on distinguishing the case from Clapper v. Amnesty International USA, which was brought by some of the same plaintiffs. The Supreme Court ruled in February 2013 – about three months before whistleblower Edward Snowden’s first leaks – that those plaintiffs could not prove their records were taken and therefore had no right to sue.

Toomey said there are several significant differences between the cases, including that the contested surveillance is different and more expansive, that more is known now about the surveillance from official sources and that plaintiffs have greater footing with the addition of global Wikimedia and defense attorneys.

Patton, however, said the cases are quite similar. The government has not confirmed details about the scope or operational details of upstream collection, he said, and the lawsuit’s claims are speculative and based on assumptions. Details about the collection have not and cannot be disclosed, he said, because the information is classified.

“There are very few pieces of information” that are public about upstream collection, he said, describing a 2014 Privacy and Civil Liberties Oversight Board report on the collection – as well as a notice of records-collection issued under Section 702 to a defense attorney – as less descriptive than Toomey suggested.

Ellis inquired about whether the plaintiffs would be better able to make their case if Snowden supplied the ACLU legal team with more documents on the collection, and seemed to express skepticism about the rigor of constitutional review from the Foreign Intelligence Surveillance Court.

“The only thing missing from that equation is anyone arguing it’s unconstitutional,” he observed about the intelligence court, which critics contend is often a rubber stamp for expansive government requests they liken to general warrants.

Patton said the only way he could see someone having a right to challenge upstream collection would be if the government admitted they had been affected in the course of criminal proceedings.

Until now, most public attention on lawsuits against NSA mass surveillance have focused on the easier-to-understand dragnet collection of domestic call records. Congress voted earlier this year to end that program, though cases against it are still ongoing, with attorneys pushing to update Supreme Court precedent on privacy rights regarding information customers provide to businesses.

Another case against upstream collection – Jewel v. NSA, brought by the Electronic Frontier Foundation – is on appeal with the U.S. Court of Appeals for the 9th Circuit after a decade of legal wrangling. Cases against the PRISM Internet program include a long-stalled lawsuit from activist attorney Larry Klayman that seeks enormous damages for alleged constitutional violations.

Steven Nelson is a reporter at U.S. News & World Report. You can follow him on Twitter or reach him at snelson@usnews.com.