With little fanfare, the National Security Agency dropped hundreds of pages worth of surveillance reports into the dead of night before Christmas Eve—some of which detailed U.S. citizens that were "inadvertently" swept up in the government's data dragnet.

As Americans were preparing to open holiday gifts, the agency quietly published a trove of declassified data spanning more than a decade of intelligence gathering. Those documents, required by the President's Intelligence Oversight Board (IOB), were heavily redacted to protect disclosures of sensitive information.

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Entire swaths of text were blanked out, making it nearly impossible to determine specific names, programs or occurrences of privacy violations. However, the documents detailed a number of instances where analysts "erroneously" gathered information on U.S. citizens, or were at least guilty of shoddy practices.

In a 2012 quarterly report, for example, an analyst "forwarded in an email to unauthorized recipients the results of a raw traffic database query that included terms associated with "an unidentified U.S. citizen. The email was recalled, the report said, without providing further information.