Ride The Lightning: How Much Data is Facebook Giving Law Enforcement Under Secret Warrants?
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Excerpts:
"That "trust" is buttressed by the fact that Facebook doesn't tell users about the warrants to give them a chance to challenge those warrants legally. Why not Facebook? Twitter (and others) have adopted a policy notifiying users of law enforcement warrants. If Facebook is as interested in user rights as it claims, it is time to rectify this omission."