The Volokh Conspiracy

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Minnesota court on the Fifth Amendment and compelling fingerprints to unlock a phone


A few months ago I wrote a long post, "The Fifth Amendment and Touch ID," on whether and how the Fifth Amendment applies when the government seeks to compel a smartphone user to unlock his phone using the fingerprint sensor. I thought I would flag a new case on the subject, State v. Diamond, decided yesterday by the Minnesota Court of Appeals. The Fifth Amendment issues are pretty technical issues, and my earlier post had all the details, so I'm going to assume familiarity with that post and go directly into the new case.

First, the easy part: The court concludes that forcing a person to place a particular finger on a phone does not trigger the Fifth Amendment because it is not testimonial. From the opinion:

By being ordered to produce his fingerprint, . . . 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. See Doe, 487 U.S. at 210, 108 S. Ct. at 2347-48.

So far, so good.

But there's a twist. The government had sought an order compelling the defendant to unlock the phone with his fingerprint. The trial court had then "ordered Diamond to provide a fingerprint or thumbprint to unlock his cellphone." Diamond refused to comply, and the trial court ruled that Diamond had no Fifth Amendment privilege and found him in contempt. The trial judge "informed [Diamond] that compliance with the order would remedy the civil contempt. Diamond provided his fingerprint, and police immediately searched his cellphone."

Here's why that matters. On appeal, Diamond argued that the government violated his Fifth Amendment rights because the government made Diamond select which finger to use. Specifically, Diamond argued 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." As I explained in detail in my prior post, I think this should change the analysis (see the discussions of Case 2 and Case 3).

The court rejected this argument in the following passage:

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."

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.

There are two suggested rationales in this explanation. First, the court suggests that Diamond was not required by the order to tell the police which fingerprint would open the phone. I'm not sure that's right, though, as it seems that Diamond was required to unlock the phone in the officers' presence—which necessarily would disclose which finger opened the phone.

Second, the court suggests that Diamond didn't object to carrying out the order. But didn't he? He raised his Fifth Amendment objection, and the court rejected it and found him in contempt. Maybe there's a kind of waiver idea operating here, by which Diamond didn't raise the specific point about which finger to use at the earlier hearing and so he can't raise it now. But given that he did assert his Fifth Amendment right at the time, I'm not sure that he should have been required to raise it a second time.

In any event, I'm not sure this difference matters to the outcome. I gather from the facts that this was known to be Diamond's phone, and if that's right the foregone conclusion doctrine should apply anyway. In the framework of my earlier post, this would be Case 3 and not Case 2. But it would at least change the analysis somewhat.