One technique Litan said has been valuable in narrowing down past terrorist activity is to compare communications from a potential terrorist's personal handset, which is usually operating without encryption, with that person's second encrypted phone, a dedicated handset for communicating with superiors. If both handsets are used in the same location, as tracked by triangulation from cell towers, the information can potentially offer clues about location and timing for a planned attack.
Litan said that even if Apple gave up encryption keys to its smartphones, there still might be encrypted data inside apps running on the phone. Encrypted apps sometimes work by recording encrypted keystrokes used in text, email and files, which would mean that breaking into an encrypted phone might yield only a string of encrypted text. "That encryption can't be broken in a timely fashion. It would take weeks," she said.
By studying a suspicious person's handset behaviors, credit card purchases and other electronic footprints -- and even voice calls -- investigators can glean a lot about a suspicious person without access to encrypted files. "Why not go after bigger-picture problems like integrating intelligence silos and stop terrorizing the tech companies?" Litan asked.
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