Whistleblowing controversies of the last decade 12 show all Whistleblowing controversies of the last decade 1/12 Edward Snowden NSA leak Articles in The Guardian revealed that the US and the UK spied government.spy.spy on foreign leaders and diplomats at the 2009 G20 summit . Reuters 2/12 WikiLeaks ' US diplomatic cables leak In 2009 , former US soldier Chelsea Manning , downloaded hundreds of thousands of classified US Government documents , and passed them on to Jullian Assange 's whistleblowing website WikiLeaks .