Britain’s most senior security official, Charles Farr, has been forced to comment on a UK government surveillance policy that exploits legal frameworks to monitor online communications. First revealed as part of the Edward Snowden leaks, Britain's Government Communications Headquarters (GCHQ) has been reportedly intercepting and storing massive amounts of data flowing across the web, including emails and posts on social media sites like Facebook and Twitter. Farr has published a detailed justification (PDF) for the UK government’s spying program, dubbed Tempora, and defended the lack of individual search warrants which are normally required to monitor internal communications between British residents.

Internal or external? That is the question

The justification centers around the use of "external communications" where data from Facebook, Twitter, Google searches, and other activity is sent by a resident within the UK to servers and data centers outside Britain. Under UK law, a specific warrant is required to monitor internal communications between British residents, but "external communications" can be monitored randomly under a general warrant. GCHQ appears to define the use of Facebook, Twitter, and other web services as "external communications," allowing, and justifying, the interception of communications in and out of Britain.

Farr’s comments come as part of a 48-page explanation in response to a case brought by Privacy International, Liberty, Amnesty International, and other civil rights groups. The case is designed to shed more light on the secret Tempora surveillance program, and clarify the vague legal frameworks used to justify its existence. "The security services consider that they’re entitled to read, listen and analyse all our communications on Facebook, Google and other US-based platforms," says James Welch, legal director of Liberty. "If there was any remaining doubt that our snooping laws need a radical overhaul there can be no longer."