"The Omnibus Crime Control and Safe Streets Act of 1968 requires the Administrative Office of the United States Courts (AO) to report to Congress the number and nature of federal and state applications for orders authorizing or approving the interception of wire, oral, or electronic communications. The statute requires that specific information be provided to the AO, including the offense(s) under investigation, the location of the intercept, the cost of the surveillance, and the number of arrests, trials, and convictions that directly result from the surveillance. This report covers intercepts concluded between January 1, 2007, and December 31, 2007, and provides supplementary information on arrests and convictions resulting from intercepts concluded in prior years. A total of 2,208 intercepts authorized by federal and state courts were completed in 2007, an increase of 20 percent compared to the number terminated in 2006. The number of applications for orders by federal authorities fell less than 1 percent to 457. The number of applications reported by state prosecuting officials grew 27 percent to 1,751, with 24 states providing reports, 1 more than in 2006. Installed wiretaps were in operation an average of 44 days per wiretap in 2007, compared to 40 days in 2006. The average number of persons whose communications were intercepted decreased from 122 per wiretap order in 2006 to 94 per wiretap order in 2007. The average percentage of intercepted communications that were incriminating was 30 percent in 2007, compared to 20 percent in 2006."
United States Courts: http://www.uscourts.gov/