Police asked 3D printing lab Arora to recreate a dead man’s fingers to unlock phone
▻http://fusion.net/story/327145/3d-print-dead-mans-fingers-to-unlock-his-phone
A 3D printed finger alone often can’t unlock a phone these days. Most fingerprint readers used on phones are capacitive, which means they rely on the closing of tiny electrical circuits to work. The ridges of your fingers cause some of these circuits to come in contact with each other, generating an image of the fingerprint. Skin is conductive enough to close these circuits, but the normal 3D printing plastic isn’t, so Arora coated the 3D printed fingers in a thin layer of metallic particles so that the fingerprint scanner can read them.
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“We don’t know which finger the suspect used,” he told me by phone. “We think it’s going to be the thumb or index finger—that’s what most people use—but we have all ten.”
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a password that you have memorized may be protected by the Fifth Amendment. Your fingerprints aren’t.
but a judge argues that
phones should be considered extensions of our minds and should be protected under the Fifth Amendment (protection against self-incrimination) and not just the Fourth Amendment (protection against illegal search and seizure). He argues that cell phones are unlike almost anything else we own.