State Appeals Court Says Unlocking A Phone With A Fingerprint Doesn't Violate The Fifth Amendment

from the giving-The-Man-the-finger-no-longer-subversive;-actually-helpful dept

As was hinted heavily three years ago, you might be better off securing your phone with a passcode than your fingerprint. While a fingerprint is definitely unique and (theoretically...) a better way to keep thieves and snoopers from breaking into your phone, it's not much help when it comes to your Fifth Amendment protections against self-incrimination.

The Minnesota Appeals Court has ruled [PDF] that unlocking a phone with a fingerprint is no more "testimonial" than a blood draw, police lineup appearance, or even matching the description of a suspected criminal. (h/t Orin Kerr)

Diamond relies on In re Grand Jury Subpoena Duces Tecum, 670 F.3d 1335 (11th Cir. 2012), to support his argument that supplying his fingerprint was testimonial. In In re Grand Jury, the court reasoned that requiring the defendant to decrypt and produce the contents of a computer’s hard drive, when it was unknown whether any documents were even on the encrypted drive, “would be tantamount to testimony by [the defendant] of his knowledge of the existence and location of potentially incriminating files; of his possession, control, and access to the encrypted portions of the drives; and of his capability to decrypt the files.” Id. at 1346. The court concluded that such a requirement is analogous to requiring production of a combination and that such a production involves implied factual statements that could potentially incriminate. Id. By being ordered to produce his fingerprint, however, Diamond was not required to disclose any knowledge he might have or to speak his guilt. See Doe, 487 U.S. at 211, 108 S. Ct. at 2348. The district court’s order is therefore distinguishable from requiring a defendant to decrypt a hard drive or produce a combination. See, e.g., In re Grand Jury, 670 F.3d at 1346; United States v. Kirschner, 823 F. Supp. 2d 665, 669 (E.D. Mich. 2010) (holding that requiring a defendant to provide computer password violates the Fifth Amendment). Those requirements involve a level of knowledge and mental capacity that is not present in ordering Diamond to place his fingerprint on his cellphone. Instead, the task that Diamond was compelled to perform—to provide his fingerprint—is no more testimonial than furnishing a blood sample, providing handwriting or voice exemplars, standing in a lineup, or wearing particular clothing.

Of course, it's what's contained in the now-unlocked device that might be incriminating, which is why Diamond pointed to In re Grand Jury as being analogous to the forced provision of a fingerprint. The court's rebuttal of this argument, however, doesn't make a lot of sense. It says the process that unlocked the device requires no knowledge or mental capacity -- which is certainly true -- but that the end result, despite being the same (the production of evidence against themselves) is somehow different because of the part of the body used to obtain access (finger v. brain).

In recounting the obtaining of the print, the court shows that some knowledge is imparted by this effort -- information not possessed by law enforcement or prosecutors.

Diamond also argues that he “was required to identify for the police which of his fingerprints would open the phone” and that this requirement compelled a testimonial communication. This argument, however, mischaracterizes the district court’s order. The district court’s February 11 order compelled Diamond to “provide a fingerprint or thumbprint as deemed necessary by the Chaska Police Department to unlock his seized cell phone.” At the April 3 contempt hearing, the district court referred to Diamond providing his “thumbprint.” The prosecutor noted that they were “not sure if it’s an index finger or a thumb.” The district court answered, “Take whatever samples you need.” Diamond then asked the detectives which finger they wanted, and they answered, “The one that unlocks it.”

This is something only Diamond would know, and by unlocking the phone, he would be demonstrating some form of control of the device as well as responsibility for its contents. So, it is still a testimonial act, even if it doesn't rise to the mental level of retaining a password or combination. (And, if so, would four-digit passcodes be less "testimonial" than a nine-digit alphanumeric password, if the bright line comes down to mental effort?)

Given the reasoning of the court, it almost appears as though Diamond may have succeeded in this constitutional challenge if he had chosen to do so at the point he was ordered to produce the correct finger.

It is clear that the district court permitted the state to take samples of all of Diamond’s fingerprints and thumbprints. The district court did not ask Diamond whether his prints would unlock the cellphone or which print would unlock it, nor did the district court compel Diamond to disclose that information. There is no indication that Diamond would have been asked to do more had none of his fingerprints unlocked the cellphone. Diamond himself asked which finger the detectives wanted when he was ready to comply with the order, and the detectives answered his question. Diamond did not object then, nor did he bring an additional motion to suppress the evidence based on the exchange that he initiated.

And so, in first decision of its kind for this Appeals Court, the precedent established is that fingerprints are less protective of defendants' Fifth Amendment rights than passwords.

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Filed Under: fifth amendment, fingerprints, minnesota, self-incrimination