The disclosure, buried in a report by the U.S. agency that oversees federal courts, also showed that authorities armed with wiretap orders are encountering more encryption than before.
The revelation comes as encryption has come front and center in the wake of the NSA Spygate scandal, and as Americans consider looking for effective ways to scramble their communications from the government’s prying eyes.
According to today’s report from the U.S. Administrative Office of the Courts:
Encryption was reported for 15 wiretaps in 2012 and for 7 wiretaps conducted during previous years. In four of these wiretaps, officials were unable to decipher the plain text of the messages. This is the first time that jurisdictions have reported that encryption prevented officials from obtaining the plain text of the communications since the AO began collecting encryption data in 2001.