NSA performed warrantless searches on Americans' calls and emails – Clapper

US intelligence chiefs have confirmed that the National Security Agency has used a "back door" in surveillance law to perform warrantless searches on Americans’ communications. The NSA's collection programs are ostensibly targeted at foreigners, but in August the Guardian revealed a secret rule change allowing NSA analysts to search for Americans' details within the databases.  Now, in a letter to Senator Ron Wyden, an Oregon Democrat on the intelligence committee, the director of national intelligence, James Clapper, has confirmed for the first time the use of this legal authority to search for data related to “US persons”.

Read more at the Guardian UK