A second lawsuit challenging the constitutionality of the NSA's dragnet phone surveillance program was lodged today in a New York federal court by the American Civil Liberties Union, calling the spying "one of the largest surveillance efforts ever launched by a democratic government."

The suit (.pdf) comes days after Larry Klayman, the former chairman of Judicial Watch, lodged what was believed to be the first suit alleging the government has illegally spied on their Verizon accounts.

The Guardian last week posted a leaked copy of a top secret Foreign Intelligence Surveillance Court opinion requiring Verizon Business to provide the NSA the phone numbers of both parties involved in all calls, the International Mobile Subscriber Identity (IMSI) number for mobile callers, calling card numbers used in the call, and the time and duration of the calls, and where the calls were made.

According to the suit by the ACLU, whose employees subscribe to Verizon:

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. 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.

Both suits allege breaches of at least the First Amendment and the Fourth Amendment.

Among others, the ACLU suit names Director of National Intelligence James Clapper, NSA Director Keith Alexander and FBI Director Robert Mueller.