The U.S. federal government (Transportation Security Administration, part of the Department of Homeland Security) has issued 5,000 letters to applicants which letters state, "I have determined that you pose a security threat." Many of the applicants don't pose a security threat. However, the government has refused requests that replacement letters be issued without the offending language. So that information is in the applicants' dossiers.
Source: "Blunt Federal Letters Tell Students They're Security Threats," by Scott Shane. The New York Times. May 13, 2008.