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25. State surveillance and data retention

This chapter examines the purpose and impacts of state surveillance in the digital environment. It considers the effects of the revelations brought to light by Edward Snowden and outlines the current legal framework for the interception of communications in the UK. The programmes of state surveillance, including by the NSA, GCHQ, and Prism are outlined. The retention and use of personal digital data is also discussed and its relation to the Investigatory Powers Act 2016 examined in detail. The chapter discusses the challenges to data interception in Liberty and Privacy International v GCHQ and against data retention in Tele2 Sverige.