SAN FRANCISCO (KGO) --A lawsuit is being filed here in Northern California related to the Paris terror attacks.
The father of the lone American citizen killed in that attack is suing tech companies here in the Bay Area for providing the social media platforms terrorists use for recruitment.
"They're just not doing enough," said Keith Altman, the lawyer representing the grieving father.
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The lawsuit alleges that Google, Facebook and Twitter are all partly responsible.
"These companies allow the terrorists to use their sites to engage in terrorist operations," said Altman.
Terrorism law experts know it's an ongoing problem and also an uphill legal battle.
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"You can't hold a company like Facebook or Twitter liable for something that someone says on the platform,' said Betsy Cooper with the U.C. Berkeley center for Long Term Cybersecurity.
o win, they'll have to prove social media posts directly caused the killings in Paris. The court papers are peppered with pictures of extremist propaganda posted online.
The plaintiffs argue the companies could do more to bring those pages down and keep them down, using the same machine learning muscle they already use to decide what content to show you.
"If they put a fraction of the effort into shutting down the terrorists as they do into figuring out what ad to show me, I think we wouldn't be having this conversation," said Altman.
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In separate statements, all three companies have said they prohibit terrorist content and remove it as soon as it's flagged by users.
"I also suspect that behind the scenes they are actually doing more. One reason that you might not want to make these things public is once you tell the terrorists how you're trying to track them down, well of course, they'll change their methods," said Cooper.
The companies have not responded to the lawsuit yet. A different judge dismissed a similar suit several months ago.
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