Civil liberties advocates and a bipartisan group in Congress stepped up pressure on Tuesday against the Obama administration’s secret domestic surveillance programs via a lawsuit and legislation that could shed light on the scope and legality of the government’s snooping.

The American Civil Liberties Union filed suit in New York federal court against the U.S. Justice Department and other federal agencies, challenging the constitutionality of the government’s review of millions of phone call records on Verizon subscribers. ACLU lawyers contend the government’s "dragnet acquisition" is likely to have a chilling effect on speech.

"The practice is akin to snatching every American’s address book — with annotations detailing whom we spoke to, when we talked, for how long, and from where," ACLU deputy legal director Jameel Jaffer said in the complaint, which alleges First Amendment violations. "It gives the government a comprehensive record of our associations and public movements, revealing a wealth of detail about our familial, political, professional, religious, and intimate associations."

On Capitol Hill, eight senators announced legislation to declassify significant opinions by the Foreign Intelligence Surveillance Act (FISA) court — the panel of judges in Washington that reviews government surveillance and search applications in national security investigations. It is also called the Foreign Intelligence Surveillance Court (FISC).

An order in April from a surveillance court judge authorizing the National Security Agency to review Verizon call records for a three-month period is at the heart of the ACLU lawsuit. The Guardian newspaper earlier this month disclosed the judge’s order, which wasn’t set for declassification until the year 2038.

FISA court orders and opinions are not ordinarily available for public review, and the court itself sits behind closed doors — no public allowed — inside the E. Barrett Prettyman U.S. Courthouse in downtown Washington. The court has the authority to publicly release its rulings, but disclosure is rare.

Some members of Congress expressed concern that the 11-judge court could be interpreting FISA and other authorities, including a provision of the Patriot Act — in ways lawmakers did not intend.

FISA opinions contain details of national security operations that should be classified, but the substantive legal interpretations should not remain under wraps, Senator Jeff Merkley (D-Ore.) said in a written statement announcing the bill. He was joined by Senator Mike Lee (R-Utah). The six cosponsors include Senate Judiciary chairman Patrick Leahy (D-Vt.).

"Americans deserve to know how much information about their private communications the government believes it’s allowed to take under the law," Merkley said.

"There is plenty of room to have this debate without compromising our surveillance sources or methods or tipping our hand to our enemies," he continued. "We can’t have a serious debate about how much surveillance of Americans’ communications should be permitted without ending secret law."

In late March, U.S. District Judge Reggie Walton, presiding judge of the surveillance court, wrote in a letter to Senate Intelligence Committee chairwoman Diane Feinstein that the preparation of public summaries of the secret court’s opinions isn’t an easy task.

"Without the full opinion, however, the summary is much more likely to result in misunderstanding or confusion regarding the court’s decision or reasoning," Walton wrote. His letter was first published by the Secrecy News blog of the Federation of American Scientists.

Walton said that "there is also the very real problem" of segregating classified information from legal analysis.

"As members of Congress who have seen the opinions know, most FISC opinions rest heavily on the facts presented in the particular matter before the court," Walton wrote. "Thus, in most cases, the facts and the legal analysis are so inextricably intertwined that excising the classified information from the FISC’s analysis would result in a remnant void of much or any useful meaning."

The ACLU and civil liberties advocate The Electronic Frontier Foundation both have pending disputes before the surveillance court over access to sealed rulings. The challengers face an uphill fight. In 2007, the court rejected an ACLU request for copies of opinions about the George W. Bush administration’s warrantless wiretapping program.

On Monday, the ACLU asked the court to unseal orders and opinions addressing the meaning and scope of Section 215 of the Patriot Act. The federal government in April was given approval to review Verizon phone records under that provision of the law.

"The government appears to have secretly given itself shockingly broad surveillance powers, thereby depriving the public of the chance to weigh in on the wisdom of an unprecedented invasion of privacy," Alexander Abdo, a staff attorney with the ACLU National Security Project, said in a written statement.

EFF lawyers have asked the surveillance court to consent to the disclosure of a lengthy ruling, published in 2011, in which the court found — at least in this instance — that government surveillance ran afoul of Fourth Amendment protections. DOJ lawyers on June 7 filed papers in the surveillance court arguing that the opinion should remain sealed. The government argued the executive branch has properly classified the opinion.

The fight for transparency wasn’t limited to the halls of Congress and federal courthouses. In a push for greater openness, Google’s lawyers on Tuesday asked the Justice Department to allow the company to publish, in greater detail, national security request data.

Chief legal officer David Drummond wrote in a letter to Attorney General Eric Holder Jr. and FBI Director Robert Mueller III that "assertions in the press that our compliance with [law enforcement] requests gives the U.S. government unfettered access to our users’ data are simply untrue."

Drummond said that Google, which already publishes some data about government demands for user information, wants to reveal FISA disclosures — both the number of requests the company receives and the scope of the demands.

"Google has nothing to hide," Drummond wrote.

Todd Ruger can be contacted at Mike Scarcella, who contributed, can be contacted at