fact-checkers to effort to keep fake news from popping up on your news feed. william la jeunesse is tracking the story from l.a. intriguing at a minimum. how will it work, william? reporter: bill, facebook says it doesn t want to be the gatekeeper or censor but 50% of the americans getting news from the news feed the company says this is responsible thing to do. it will work three ways. users can flag a story they think it flag, if there is complaint the story is flag and sent to third party fact-checkers, politifact and doubtful that story is labeled disputed. facebook is changing the way it works to marginalize click bait, sensational headlines that grab readers and stop automated ads that rewarded fake news. will it work? bill: some say is there a danger here and is it necessary? well, you could argue that fake news is a fake story.