Last week, The Washington Post published the results of a huge investigation into NSA records leaked by Edward Snowden. Based on tons of data, the paper asserted that ninety percent of messages intercepted by the NSA came from U.S. citizens and non-targets. Today, Post reporter Barton Gellman gives us an inside look into exactly what they saw in those NSA records, why they reported what they did, and the decisions they had to make in covering the leak. It's a fascinating read, both for what it reveals about the NSA and to give an appreciation of the ethical dilemmas in reporting these events. Check out the whole report here.