There are serious obstacles that impede the Government's ability to create these electronic dossiers themselves. It requires both huge resources and expertise. Various statutes enacted in the mid-1970s -- such as the Privacy Act of 1974 -- impose transparency requirements and other forms of accountability on programs whereby the Government collects data on citizens. And the fact that much of the data about you ends up in the hands of private corporations can create further obstacles, because the tools which the Government has to compel private companies to turn over this information is limited (the fact that the FBI is sometimes unable to obtain your "transactional" Internet data without a court order -- i.e., whom you email, who emails you, what Google searches you enter, and what websites you visit --is what has caused the Obama administration to demand that Congress amend the Patriot Act to vest them with the power to obtain all of that with no judicial supervision).
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