A federal judge could grant a preliminary injunction blocking some National Security Agency surveillance programs as early as Monday.

U.S. District Court Judge Richard Leon will consider oral arguments for and against a broad preliminary injunction request Nov. 18 in Washington, D.C., during a hearing that pits Department of Justice lawyers against Larry Klayman, a former Reagan administration prosecutor who leads the advocacy group Freedom Watch.

Leon expressed a sense of urgency in scheduling the hearing and made comments that could be construed as favorable to opponents of NSA surveillance.

Klayman filed two class-action lawsuits in June after documents leaked by Edward Snowden revealed the NSA collects the phone records of millions of Americans using secret court orders and vast quantities of Web data with its PRISM program.

During an Oct. 31 status conference Leon told government lawyers: "I don't want to hear anything about vacations, weddings, days off. Forget about it. This is a case at the pinnacle of public national interest, pinnacle. All hands 24/7. No excuses."

He brushed off an apparent government bid to slow the case, saying: "the Department of Justice, the NSA and the allied government agencies that have an interest in this have had four months to think through its position. That's a lot of time."

But there are also signs Leon may not grant an injunction.

Klayman was unable to travel from California to D.C. in time for the Oct. 31 status conference and a transcript of the hearing makes clear Leon's annoyance with his solo preparation. Leon noted he had denied requests by Klayman for continuances.

The American Civil Liberties Union is also suing to stop the NSA phone-record collection.

Leon scheduled the Nov. 18 hearing after U.S. District Court Judge William Pauley scheduled Nov. 22 oral arguments for the ACLU's preliminary injunction request.

The ACLU case, which is being heard in New York, is more tailored. That lawsuit objects to the collection of Verizon phone metadata by the NSA.

Both the ACLU and Klayman argue the NSA is exceeding its authority under the law. Section 215 of the Patriot Act is used by the government to justify its collection of all Americans' phone records. Section 702 of the Foreign Intelligence Surveillance Act is cited to justify the PRISM program.

NSA surveillance programs are already reviewed by the Foreign Intelligence Surveillance Court, but all relevant case documents and rulings were secret until the Snowden leaks. Many remain classified.

A common criticism of FISC is that it produces secret legal interpretations that are not even available to lawmakers who wrote the legislation decisions are based on. Patriot Act author Rep. Jim Sensenbrenner, R-Wisc., for example, says the NSA lacks authority under his 2001 law to collect the phone records of all Americans and he's sponsoring legislation to explicitly forbid it.

"I am going to be very curious to hear the arguments about the authority this court has to review or overrule a decision by another court," Leon said Oct. 31. "I don't know what Mr. Klayman's theory is going to be just yet, but we will see."

Nick Dranias, director of the Goldwater Institute's Center for Constitutional Government, says Leon likely does have the power to review FISC cases.

"I don't think the court should have any problem taking jurisdiction over this," Dranias said. "I would think you could make a pretty plausible argument that a genuine full-fledged Article III court would have primary jurisdiction over constitutional issues, particularly when you have real litigation going on, as opposed to a more administrative judicial role."

Dranias, who has argued before the Supreme Court, said "my argument would be that the FISA court would not be a full and fair litigation of the underlying constitutional issues because you don't have an adversarial process" and also that "the Constitution directly vests Article III courts with the power to decide constitutional issues."

Another bid for judicial review of the FISC's approval of phone record collection is being pursued by the Electronic Privacy Information Center. The U.S. Supreme Court is considering during a Friday conference meeting a request for direct intervention from EPIC that would bypass lower courts.

The preliminary injunction hearing on Monday will address both the Internet and phone-related lawsuits filed by Klayman. Although the two cases have not been joined, attorneys are filing one set of briefs in advance. Leon set a Nov. 11 deadline for the government to submit its arguments.

The preliminary injunction is sought pending final resolution of the cases, which demand a permanent end to the programs and steep financial penalties.

In addition to his pre-hearing comments, Leon's resume may also be seen by NSA opponents as a reason to be hopeful.

Several of Leon's well-known rulings have proscribed federal authority. In 2012 he ruled grisly Food and Drug Administration labels on cigarette packs would violate the First Amendment. In the first ruling of its kind Leon ordered in 2008 the release of five Algerian men held at Guantanamo Bay since 2002 after finding a lack of evidence they were terrorists. He dismissed the government's reliance on a classified document attributed to an unnamed source.

Leon was appointed to the U.S. District Court for the District of Columbia in 2001 by President George W. Bush, and took office in 2002. He previously served as a top Justice Department official and as an attorney advising congressional probes into the Iran Contra scandal of the 1980s and the Whitewater controversy of the 1990s.

"We are hopeful that the court will preliminarily enjoin the government from continuing to perpetrate massive violations of the Constitution," Klayman told U.S. News. The NSA programs, he said, are "not focused solely on spying on terrorists and terrorist groups, but instead all of the citizenry."