Yesterday, the WaPo published an interview with Barry Steinhardt of the American Civil Liberties Union about Matrix and other U.S. government data-mining programmes. Seinhard says that “according to a Government Accounting Office study being released today (PDF) there are, at least, 199 government data mining programs. 54 of those use private data. That may only be the tip of the iceberg because GAO had to rely primarily on self reporting by the agencies and the intelligence agencies would not report at all.”