As reported by the Washington Post, Edward Snowden denies in no uncertain terms the idea that he failed to go through proper channels
to expose what he thought were troubling privacy violations being committed by the NSA, and that he observed as a contractor employed by the agency. The article begins: "[Snowden] said he repeatedly tried to go through official channels to raise concerns about government snooping programs but that his warnings fell on the deaf ears. In testimony to the European Parliament released Friday morning, Snowden wrote that he reported policy or legal issues related to spying programs to more than 10 officials, but as a contractor he had no legal avenue to pursue further whistleblowing."
Further, "Elsewhere in his testimony, Snowden described the reaction he received when relating his concerns to co-workers and superiors. The responses, he said, fell into two camps. 'The first were well-meaning but hushed warnings not to "rock the boat," for fear of the sort of retaliation that befell former NSA whistleblowers like Wiebe, Binney, and Drake.' All three of those men, he notes, were subject to intense scrutiny and the threat of criminal prosecution."