Citizenfour is an Academy Award winning documentary on the story of Edward Snowden. He was a contractor for the NSA as a systems administrator working out of Hawaii, and that's how he was able to obtain information. What he did with that information is what became so controversial. He went to Hong Kong, and contacted journalists to give them this information he had collected, but didn't want anything released that would risk the lives of government operatives. Instead, he wanted journalists to tell the world, Americans in particular, what the NSA had been up to.
Edward Snowden's actions may be controversial, but what is not controversial is the material itself that had been leaked. It's Leo's opinion that he's done a very important thing -- he took something that was done in secret, without the permission of the American people, and brought that information to the forefront so we can have a national discussion about it.
Find out more about Citizenfour, and watch the trailer for it, at citizenfourfilm.com.