Widespread digital encryption presents a massive challenge to law enforcement, FBI Director James Comey told lawmakers on Wednesday, urging Silicon Valley to come up with a solution.
"Our job is to look at a haystack the size of this country to find needles that are increasingly invisible to us because of end-to-end encryption," Comey told the U.S. Senate Committee on the Judiciary.
The U.S. government has been criticized by privacy advocates and tech firms for requesting a "back door" to access private user data on encrypted systems — a measure that could leave that same technology open to hackers.
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Comey warned that criminals could use encrypted communications to avoid surveillance and that ISIL was using the technology to recruit members.
"This is not your grandfather's al-Qaeda," Comey said.
Silicon Valley companies have mostly been opposed to giving law enforcement this kind of access. Comey warned that fully encrypted communications — which only allow the sender and recipient of a message to read it — left criminal investigators in the dark.
"People watch TV and think the FBI has a way to break that encryption," Comey said. "We do not."