The office collects the figures from federal and local jurisdictions at the request of Congress, but does not interpret the statistics. There is no explanation of why the federal figures increased so much, and it is generally out of line with the number of wiretaps between 1997 and 2009, which averaged 550 annually. A large number of wiretaps was also reported in 2010, when 1,207 were secured.
“This is just one more piece of evidence demonstrating the need for a full, informed public debate about the scope, breadth, and pervasiveness of government surveillance in this country,” Mark Rumold, a staff attorney at the Electronic Frontier Foundation, said in an e-mail. “We have a secret surveillance program churning in the background, sweeping in everyone’s communications, and, at the same time, in the shadows (and frequently under seal), law enforcement is constantly expanding its use and reliance on surveillance in traditional criminal investigations.”
The Justice Department did not respond to requests for comment.
A single wiretap can sweep up thousands of communications. One 30-day local wiretap in California, for instance, generated 185,268 cellular telephone interceptions, of which 12 percent were incriminating, according to the report.
The vast majority of the wiretaps in both federal and state cases were obtained as part of drug investigations, and they overwhelmingly were directed at cellphones, according to the report. Only 14 court orders were for personal residences.
Most jurisdictions limit the period of surveillance to 30 days, but extensions can be obtained. In one case, a narcotics investigation in Queens, the wiretap continued for 580 days. The longest federal wiretap was also a drug case and lasted 180 days in the Western District of Washington state, which includes Seattle.
There were 25 authorized federal wiretaps in the District in 2012, 18 in Virginia and 12 in Maryland. Local authorities in Maryland reported 50 wiretap orders issued by state judges, including 34 in Harford County. Virginia’s attorney general reported nine orders.
The amount of encryption being encountered by law enforcement authorities is also increasing, and for the first time, “jurisdictions have reported that encryption prevented officials from obtaining the plain text of the communications,” the report noted.
Officials said 3,743 people were arrested as a result of the interceptions in 2012, and so far 455 have been convicted.