Bates said that the court had previously approved NSA requests based on the agency's description of its data collection practices, but noted with frustration that the description kept changing. The court initially understood that the NSA's technical measures would prevent the acquisition of domestic content, but later discovered that those measures were inadequate, Bates said in his opinion.
"The Court is troubled that the government's revelations regarding NSA's acquisition of Internet transactions marks the third instance in less than three years in which the government has disclosed a substantial misrepresentation regarding the scope of a major collection program," the opinion notes.
A footnote pointed to similar inconsistencies in the NSA's description of its phone metadata collection activities. "Contrary to the government's repeated assurances, NSA had been routinely running queries of the metadata using querying terms that did not meet the standard for querying." The querying standard had been "so frequently and systematically violated" that it never worked effectively, the court noted.
Such facts fundamentally alter the statutory and constitutional basis for the data collection, Bates said in the opinion.
In a statement referencing the October 2011 FISA opinion, the Office of the Director of National Intelligence said the problems stemmed from an incomplete understanding of data collection technology. "These incidents were due to a variety of factors, including gaps in technical understanding among various NSA components about how certain aspects of the complex architecture supporting the programs functioned."
Those gaps led to an unintended misrepresentation of the manner in which the NSA collected data, the statement said. It noted that after the issue was discovered, steps were take to minimize data collection and ensure that it was more targeted.
Jaikumar Vijayan covers data security and privacy issues, financial services security and e-voting for Computerworld. Follow Jaikumar on Twitter at @jaivijayan or subscribe to Jaikumar's RSS feed. His email address is email@example.com.
Read more about privacy in Computerworld's Privacy Topic Center.