Newsweek is reporting the FBI has used a secret warrant to raid the home of a former Justice Department lawyer named Thomas Tamm. During the raid, FBI agents seized three computers and personal files. According to Newsweek the FBI is trying to determine who leaked details of the government’s secret warrantless eavesdropping program to the news media. Tamm left the department last year. He had worked in the Office of Intelligence Policy and Review, a unit that oversees surveillance of terrorist and espionage targets.