Homeland Security officials are testing a supersnoop computer system that sifts through personal information on U.S. citizens to detect possible terrorist attacks, prompting concerns from lawmakers who have called for investigations. The system uses the same data-mining process that was developed by the Pentagon's Total Information Awareness (TIA) project that was banned by Congress in 2003 because of vast privacy violations. A Government Accountability Office (GAO) investigation of the project called ADVISE -- Analysis, Dissemination, Visualization, Insight and Semantic Enhancement -- was requested by Rep. David R. Obey, Wisconsin Democrat and chairman of the House Appropriations Committee. The investigation focuses...