Sen. Mark Udall (D-CO) on Friday called on Congress to amend legislation that authorized dragnet-style warrantless wiretapping by the National Security Agency.

The FISA Amendments Act of 2008 gave the government broad powers to monitor international phone calls and emails, and granted legal immunity to telecommunication companies that had participated in the the Bush administration's wiretapping program prior to 2008. The law was set to expire in 2012. However, the Senate Select Intelligence Committee in May approved the FAA Sunsets Extension Act to extend the law for another five years.

"I opposed the committee's decision to approve a long-term extension of the federal government's warrantless surveillance program, because I believe that Congress and the American people need a better understanding of how the program has affected the privacy of American citizens - in particular, an estimate of how many Americans have had their phone calls and e-mails collected under this law," Udall said.

"Absent this understanding, Congress should not simply extend the law for five years without changes. The FISA Amendments Act has yielded important intelligence and should be continued, but we need more information about its impact so that Congress can consider whether privacy protections should be clarified or strengthened. I also believe we need to put in place new protections against warrantless searches for Americans' communications."

The Foreign Intelligence Surveillance Act (FISA) was originally enacted by Congress to prevent the worst abuses of the Nixon administration from ever occurring again. The law established the FISA court, which regulates the government’s conduct of intelligence surveillance inside the United States and generally requires the government to seek warrants before monitoring communications.

But civil liberties advocates have warned the FISA court has become an informational black hole. Since the FAA passed act passed, the FISA court has continued to operate in complete secrecy with greatly enhanced authority to approve dragnet-style surveillance, yet it has released less than two pages of information on their activities every year since.

In committee, Udall and Sen. Ron Wyden (D-OR) proposed requiring an Inspector General (IG) audit to estimate the number of people inside the United States who have had their communications reviewed. They also pushed to restate that the law may not be used to intentionally acquire the communications of U.S. persons without a warrant. But neither amendment to the FAA Sunsets Extension Act of 2012 was approved.

With prior reporting by Stephen C. Webster

[Digital surveillance image via Shutterstock]