Ever since Edward Snowden's leaks came to light, UK spy agencies have responded to accusations of surveillance overreach with a common boilerplate statement: that their activities are lawful, necessary and proportionate. However, they can't always use that justification any more. The Investigatory Powers Tribunal has ruled that key GCHQ, MI5 and MI6 bulk data collection programs violated privacy protections in the European Convention on Human Rights. Both a Bulk Communications Data effort (which covers data such as visited websites, email metadata and GPS locations) and a Bulk Personal Datasets initiative (covering biographical details like your communications and financial activities) didn't have proper oversight until 2015, when some safeguards came into place. That's particularly damning when BCD was had been in place since 1998, and BPD since 2006.