The bureau’s wish list calls for the system to be able to automatically search “publicly available” material from Facebook, Twitter and other social media sites for keywords relating to terrorism, surveillance operations, online crime and other FBI missions. Agents would be alerted if the searches produce evidence of “breaking events, incidents, and emerging threats”.
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Lynch says that many people post to social media in the expectation that only their friends and followers are reading, which gives them “the sense of freedom to say what they want without worrying too much about recourse,” says Lynch. “But these tools that mine open source data and presumably store it for a very long time, do away with that kind of privacy. I worry about the effect of that on free speech in the US”.