Washington -Congress is investigating a "serious" failure by the National Security Agency to comply with legal limits on its domestic eavesdropping activities, key lawmakers said Thursday.
An internal review by the Justice Department and the NSA found that the spy agency's monitoring program had exceeded limits set by Congress last year designed to protect the privacy of U.S. citizens. The Justice Department said that steps have been taken to correct the problem, discovered as the Obama administration was preparing to seek renewal of the surveillance program.
"We haven't found any evidence that anyone at NSA had deliberately broken the law," said Rep. C.A. Dutch Ruppersberger, who chairs a House Intelligence subcommittee that oversees the NSA.
The Baltimore County Democrat said his panel has held four classified briefings on the matter and is continuing its investigation.
Separately, the chairman of the Senate Intelligence Committee described details of the NSA's "overcollection" of domestic communications, first reported in The New York Times, as "serious allegations." Sen. Dianne Feinstein, a California Democrat, said her committee "is looking into this, and we will hold a hearing on this subject within one month."
Ruppersberger, in an interview, described the NSA's breach as "a serious failure to comply with the FISA court."
Before the NSA can eavesdrop on the private communications of Americans suspected of involvement in terrorist activity, it is generally required to obtain a warrant from the Foreign Intelligence Surveillance Act court.
However, legislation approved last fall gave the NSA the right to conduct warrantless eavesdropping on the enormous volume of international communications that passes through the U.S. every day.
The NSA and its intelligence partners in more than 30 countries monitor over a billion communications daily, on average, including e-mail, phone calls and other records, said Ruppersberger.
What remains unclear, according to the congressman and others, is the extent of potential privacy violations. Beyond the surveillance of known or suspected terrorists under FISA warrants, the NSA's eavesdropping program is believed to focus mainly on patterns of communications that could turn up evidence of potential threats.
The bulk of the data collected by the NSA's highly classified program is believed to involve communication "envelopes," rather than the content of e-mails or phone conversations, for example.
