http://www.washingtonpost.com/blogs/the-switch/wp/2018/06/19/cambridge-analytica-whistleblower-christopher-wylie-warns-that-facebook-targeting-threatens-free-speech/

The whistleblower who outed Cambridge Analytica for improperly accessing millions of Facebook users’ personal information warned on Tuesday that unchecked data collection and targeting on social media threaten web users’ privacy – and the healthy function of democracy.

Christopher Wylie, who worked at the consultancy before it assisted President Trump’s 2016 campaign, pointed to Facebook’s tools that allow political candidates, advertisers and others to reach discrete categories of Americans online. Their narrowly tailored and delivered messages, he said at an event hosted by The Washington Post, “erode the public forum” because they allow some in politics to “go to every one of you in the audience and whisper you something. And you don’t know what I’m telling this person versus that person.”