Full disclosure: I helped out with the event. The speech itself was recorded May 15 in conjunction with Philosophy Talk, the radio show. E. Snowden begins at minute 12.
Usually, we invite famous cognitive scientists (2014: D. Hofstadter, 2013: A. Gopnik, 2012: Marvin Minsky), but E. Snowden was chosen after consultation with the studentry.
https://soundcloud.com/philosophytalk/edward-snowden-and-the-ethics-of-whistleblowing
Blurb from Symsys: https://symsys.stanford.edu/viewing/htmldocument/13638