Suspect Must Unlock Phone with Fingerprint, Judge Rules

Locking your smartphone with a fingerprint is usually more secure than locking it with a passcode — until you reach a court of law, that is. A court in Virginia has ruled that while police cannot force someone to unlock a phone with a password, they can indeed require a suspect to unlock it with a fingerprint scan.

The Virginian-Pilot of Norfolk, Virginia reports that a paramedic named David Baust has been accused of domestically abusing his girlfriend, and key evidence in the case may reside on his smartphone. The smartphone is locked with Baust's fingerprint, but Judge Steven C. Frucci has ruled that police can compel Baust to give up his fingerprint so police can try to unlock the device.

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The make and model of the phone in question were not identified in the newspaper story, and detailed case records do not appear to be available online, but the only widely used smartphones that offered fingerprint locking at the time of the original domestic-abuse charges in February 2014 were the Apple iPhone 5s and the HTC One Max.

Frucci ruled that while he could not compel Baust to divulge his or her passcode, because that would violate Baust's Fifth Amendment rights against self-incrimination, he noted that a fingerprint is a routine part of most criminal investigations. (Other court rulings have ruled that defendants can be forced to give up passwords, and the legal issue is far from resolved.)

Just as the police can take a fingerprint or DNA sample against a defendant's will, Frucci reasoned, so too can they use a fingerprint to unlock a smartphone.

Bear in mind that even though police can now use Baust's fingerprint to unlock his smartphone, the reasons why are rather tenuous. Baust had video equipment in his bedroom, and the police believe it is possible (but not definite) that some of these videos may now reside on his phone.

Furthermore, if Baust does have a passcode in addition to a fingerprint lock, the police will not legally be able to access his phone, at least not per Frucci's ruling. Prosecutors could still appeal Frucci's decision in an effort to find a judge who disagrees about the Fifth Amendment status of the passcode.

Although the Circuit Court's ruling only applies to Princess Anne County, under Virginia law the ruling can set a legal precedent for the entire state. Other states and the federal government are not bound by the ruling, so it remains to be seen how the issue of fingerprint-vs.-passcode self-incrimination will play out in various jurisdictions across the country.

Marshall Honorof is a Staff Writer for Tom's Guide. Contact him at Follow him @marshallhonorof and on Google+. Follow us @tomsguide, on Facebook and on Google+.

Marshall Honorof

Marshall Honorof is a senior editor for Tom's Guide, overseeing the site's coverage of gaming hardware and software. He comes from a science writing background, having studied paleomammalogy, biological anthropology, and the history of science and technology. After hours, you can find him practicing taekwondo or doing deep dives on classic sci-fi.