Police Request 3D-Printed Copy of a Dead Man’s Fingers to Unlock His Smartphone

No more guessing passwords

3D Printed Hand
a2gemma via Flickr CC

Earlier this year, Apple and the FBI got in a highly-publicized court battle over whether the tech company should be required to help unlock an iPhone belonging to the perpetrators of the San Bernardino shootings. While the FBI dropped the case after finding another way to decrypt the phone, it raised privacy concerns about how law enforcement can legally access the smartphones of victims and suspects alike. Now, police are hoping that cracking into another smartphone might help solve a murder case—and they want to do it by 3D printing a dead man’s fingers, Rose Eveleth reports for Fusion.

In addition to password locks, many new smartphones are equipped with fingerprint scanners that allow their owner to bypass the pesky process of typing in their passcode over and over again. And while a federal judge in the Virginia Circuit Court ruled that police can’t force criminal suspects to give up their passwords, officials can require them to use their fingerprints to unlock their phones, Reed Albergotti wrote for the Wall Street Journal. The judge ruled that while the Fifth Amendment protects people from giving up self-incriminating evidence, such as passwords, fingerprints and other biometric data aren’t covered by pleading the Fifth under the law.

Back in June, law enforcement officers got in touch with Anil Jain, a professor at Michigan State University. Jain is a computer scientist who usually works on ways to make biometric scanners, such as fingerprint and face recognition systems, harder to hack. But the police had a different kind of request. They were working on a murder case, and had reason to believe the victim may have had important clues stored on his phone, Eveleth reports. So they asked Jain and his PhD student Sunpreet Arora, to make 3D printed copies of the dead man’s fingers so they could try to unlock the phone.

“We don’t know which finger the suspect used,” Jain tells Eveleth. “We think it’s going to be the thumb or index finger—that’s what most people use—but we have all ten.”

Since this is such a new application of 3D printing, Arora and Jain are still working out some of the kinks. For example, most fingerprint scanners built into smartphones create an image of the user’s fingerprint by relying on the ridges in their skin to complete tiny electrical circuits. However, since the plastic used in most 3D printers doesn’t conduct electricity, Arora coated the fake fingers in a layer of conductive metallic particles, Eveleth reports.

The researchers still haven’t handed the fingers to police, and it’s unclear whether they will work as many phones require a passcode when the fingerprint scanner hasn’t been used for a few days, Angela Chen writes for Gizmodo. However, while there’s no legal worries about the deceased victim incriminating himself in the eyes of the law, it’s possible this technology could be used to get around the Fifth Amendment argument against a suspect handing over their password. If all the cops need is a fingerprint to unlock a phone, they would just need to convince a judge to let them 3D print a copy in order to search it.

With this in mind, perhaps an old-fashioned password may be the safest way to keep your data on lockdown.

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