The American Civil Liberties Union (ACLU) filed a lawsuit Tuesday against four high-level government officials, arguing that? Verizon’s ongoing sharing of telephone metadata to the National Security Agency ?(NSA)?is unconstitutional.

The officials include Director of National Intelligence James Clapper, Secretary of Defense Chuck Hagel, Director of the FBI Robert Mueller, and Attorney General Eric Holder.

The ACLU is asking a federal judge to declare the entire program?unlawful, halt it, and purge all related records?admittedly a tall order.

The ACLU's? legal filing (PDF) states that the disclosure of what numbers were called and when could potentially damage the group in future advocacy work.

The government’s surveillance of their [the ACLU's] communications (hereinafter “Mass Call Tracking”) allows the government to learn sensitive and privileged information about their work and clients, and it is likely to have a chilling effect on whistleblowers and others who would otherwise contact Plaintiffs for legal assistance. This surveillance is not authorized by Section 215 and violates the First and Fourth Amendments. Plaintiffs bring this suit to obtain a declaration that the Mass Call Tracking is unlawful; to enjoin the government from continuing the Mass Call Tracking under [Verizon’s] order or any successor thereto; and to require the government to purge from its databases all of the call records related to Plaintiffs’ communications collected pursuant to the Mass Call Tracking.

Christopher Allen, a spokesperson for the FBI, told Ars that “per policy the FBI does not comment on pending legal matters.”

"This dragnet program is surely one of the largest surveillance efforts ever launched by a democratic government against its own citizens,"?ACLU Deputy Legal Director Jameel Jaffer said in a statement. "It is the equivalent of requiring every American to file a daily report with the government of every location they visited, every person they talked to on the phone, the time of each call, and the length of every conversation. The program goes far beyond even the permissive limits set by the Patriot Act and represents a gross infringement of the freedom of association and the right to privacy."

A tough legal road

Similar lawsuits challenging government spying and related laws have been filed?previously?by civil liberties groups, including the ACLU, but have had limited success in court.

In February 2013, the Supreme Court ruled in a 5-4 decision that a group of plaintiffs, including the ACLU, could not sue the government because they lacked standing as they could not definitively prove that they were being monitored.

"Respondents cannot manufacture standing merely by inflicting harm on themselves based on their fears of hypothetical future harm that is not certainly impending," Justice Samuel Alito famously wrote in the majority opinion.

However, now that Verizon’s substantial metadata disclosure has already taken place, it remains unclear whether that could?months, or even years from now?change the Supreme Court’s mind.

A related case, Jewel v. NSA , was heard before a federal judge in San Francisco in December 2012? government lawyers argued forcefully that the case couldn't move forward without violating the state secrets privilege. Meanwhile, in March 2013, the Electronic Frontier Foundation argued before a federal judge in Oakland that the government should be compelled to produce its documents detailing the interpretations of Section 215 of the Patriot Act.

Hanni Fakhoury, a staff attorney at the Electronic Frontier Foundation, told Ars that the courts may start turning their way.

"Here, where there is clearly standing since the ACLU is a Verizon Business Customer, and where information has been publicly disclosed via the Guardian and confirmed by DNI Clapper, President Obama, and congressmen, I'm hopeful this suit will go a long way towards shedding light on these surveillance programs and reinforce that our laws prohibit this blanket data collection," he said.