“[T]his Court holds that compelling an individual to scan their biometrics, and in particular their fingerprints, to unlock a smartphone device neither violates the Fourth nor Fifth Amendment. Accordingly, the Court has signed and authorized the government’s warrant, including the authority to compel fingers and thumbs to be pressed on the iPhone home button in an attempt to unlock the device.” In the Matter of the Search Warrant Application for the Cellular Telephone in United States v. Barrera, 2019 U.S. Dist. LEXIS 202935 (N.D. Ill. Nov. 22, 2019):
In analyzing this issue, the key questions, in this Court’s view, are threefold: (1) whether the biometric unlock is more like a key than a combination; (2) whether the biometric unlock is more like a physical act than testimony; and (3) whether the implicit inferences that arise from the biometric unlock procedure is sufficient to be of testimonial significance under the Fifth Amendment.
1. Key Versus Combination
First, the Court holds that the biometric unlock procedure is more akin to a key than a passcode combination. The Supreme Court in Doe, and later in Hubbell, has illustrated the difference between testimonial and non-testimonial physical acts via this helpful comparison, which aptly applies to an iPhone that has two different unlock features — a fingerprint and a passcode. In Doe, the Court noted that the Fifth Amendment permits the government to force an individual to surrender a key to a strongbox containing incriminating documents, but not to reveal the combination to a subject’s wall safe. Doe, 487 U.S. at 210 n.9. Thus, using the Doe framework, this Court examines whether a biometric scan of an individual’s finger or thumb is more like a key or a combination. See id.
A combination passcode requires a verbal statement from the possessor of the code. Doe, 487 U.S. at 211. More importantly, compelling someone to reveal a passcode also requires an individual to communicate something against her will that resides in her mind. See Holt, 218 U.S. at 252-53. A key, however, is a physical object just like a finger — it requires no revelation of mental thoughts. Nor does a finger require a communication of any information held by that person, unlike a passcode. In fact, the application of a finger to the home button on a iPhone “can be done while the individual sleeps or is unconscious,” and thus does not require any revelation of information stored in a person’s mind. Google Pixel 3 XL Cellphone, 398 F. Supp. 3d at 794.
The Supreme Court further expanded on this key/passcode distinction in Hubbell holding that reviewing and producing documents required the extensive use of the responding party’s mind in determining what was responsive. Hubbell, 530 U.S. at 43. The assembly of responsive documents was found to be more akin to providing the combination of a safe rather than surrendering a key. Id. In contrast, in the case of a finger and its corresponding print, the compelled party is not assembling anything or disclosing any mental revelations from the act. Further, the Supreme Court has recognized that “both federal and state courts have usually held that it offers no protection against compulsion to submit to fingerprinting, photographing, or measurements, to write or speak for identification, to appear in court, to stand, to assume a stance, to walk, or to make a particular gesture.” Schmerber, 384 U.S. at 764. These precedents firmly establish, in the Court’s view, that a feature of the human body, such as a finger, is an object analogous to a key — another physical object, and not a passcode. In other words, in the context of an iPhone, a finger is a modern substitute for a key.
2. Physical Act Versus Testimony
Second, the biometric procedure is first and foremost a physical act. It utilizes a body part on an individual to perform an act—rather than any implicit or explicit verbal statement. Put another way, the biometric feature is a body part used to essentially determine whether an item of evidence for a case (i.e. a cell phone) has any evidentiary value — much like a blood sample, voice exemplar, or blouse is used to determine whether it matches the blood, voice, or physical characteristics of a suspect that would provide evidentiary value in a case. As the Supreme Court appropriately stated in Wade, compelling an individual to exhibit his person to the government before trial does not violate the Fifth Amendment because such a forcing is “compulsion of the accused to exhibit his physical characteristics, not compulsion to disclose any knowledge he might have.” Wade, 388 U.S. at 222.
The Supreme Court has held that in situations that require a person to be compelled to speak, a circumstance that is often equated with the concepts of witness and testimony, the distinction between testimonial and non-testimonial still applies. As discussed above, the provision of a voice exemplar in Dionisio, an act that requires a verbal statement by the accused, was deemed non-testimonial because it did not constitute a revelation of someone’s mental thoughts, but simply a physical characteristic of a person — his voice. Dionisio, 410 U.S. at 7; see also Pennsylvania v. Muniz, 496 U.S. 582, 591, 110 S. Ct. 2638, 110 L. Ed. 2d 528 (1990) (slurring of speech evidence deemed non-testimonial because it revealed the physical manner of how a person articulates words). The concept of a fingerprint scan is a significantly less difficult Fifth Amendment issue than the recitation of words by a person under compulsion.
The question of whether a physical act is testimonial is further addressed in the act of production line of cases, as discussed above. In the act of production line of cases, the selection of the documents in response to a subpoena provides some degree of insight into the responding party’s mind, which leads to the conclusion that the production has testimonial significance. Hubbell, 530 U.S. at 43. That conclusion is not present when a biometric feature merely provides access to the entirety of the cell phone, without any selection process on the part of the compelled party. Furthermore, the government selects the fingers or thumbs to impress on to the phone, not the defendant. This further supports a finding that the compelled party’s thoughts are not being used in the process.
In addition, as the Supreme Court recognized in Doe, a physical act that does not directly point the government to incriminating evidence does not constitute a testimonial act. Doe, 487 U.S. at 215. The Doe Court held that compelling a defendant to sign a directive consenting to the disclosure of any bank accounts that he had the right of withdrawal without acknowledging the existence of any account, was not testimonial under the Fifth Amendment. Id. at 214-18. As explained by the Doe Court, as long as the government must locate the evidence on its own (as it had to with the obtention of bank records in Doe), the act of signing the consent has no testimonial significance. Id. at 215-16. Similarly, the compelled biometric unlock procedure merely gives access to a potential source of evidence; it does not tell the government where to look. Cf. Hubbell, 530 U.S. at 41-42 (the collection and production of 11 categories of documents essentially required a responding party to answer a series of interrogatories that would disclose the existence and location of particular documents fitting the descriptions). Remarkably, the potential sources of evidence in a cell phone far exceed those available in any bank record production involved in Doe — on average, an Apple iPhone can hold between 16GB and 512GB of data, and in vastly different formats — videos, photos, texts, notes, chats, location data, and data embedded within a multitude of other applications. In other words, the government’s hunt for evidence in the contents of a cell phone requires a much deeper dive than that of the bank account records in Doe, making the argument that a biometric unlock is testimonial even less persuasive.
Another concern that has been raised under the act of production doctrine is that the compelled production of the fingerprint permits the implication that the data on the phone is authentic. See, e.g., Fisher, 425 U.S. at 412-13 (discussing whether taxpayer’s act of producing documents would authenticate the documents produced). More specifically, the act of producing data in response to a subpoena may allow a court to admit the records as authentic because they came from the responding party, who determined that they were responsive, and the proponent can contend the “item is what the proponent claims it is.” Fed. R. Evid. 901(a). In contrast, the authenticity of the material obtained as a result of the biometric unlock procedure does not rest on the shoulders of the compelled party. Rather, in the context of data obtained from search warrants, courts routinely rely upon the government’s chain of custody testimony to establish the foundation for the authenticity of the items seized from a search. The fact that an individual is able to unlock a phone with a physical characteristic does not automatically make each individual set of data, such as photos, videos, notes, email, texts, etc., immediately authentic. Thus, another rationale for the act of production doctrine applying to fingerprints is not implicated here.
3. Implicit Inferences
Third, the Court holds that the implicit inference from the biometric unlock procedure, that the individual forced to unlock had some point accessed the phone to program his or her fingerprint, is not sufficient to convert the act to testimonial. The Supreme Court considered this similar concept in Doe, when it found that requiring a petitioner to execute a consent directive that would result in the production of bank records would not have testimonial significance. Doe, 487 U.S. at 214-18. This was true even when the Court found that petitioner doing so, and by allowing the bank to respond to the subpoena, would result in making an implicit declaration that the accounts belong to the petitioner. Similarly, the Supreme Court has permitted compulsions of handwriting exemplars despite the resulting implicit inference that the subject “admits his ability to write and impliedly asserts that the exemplar is his writing.” Fisher, 425 U.S. at 411. No different with the concept of a physical key — by forcing an individual, pursuant to a warrant, to hand over the key to a strongbox, it allows a firm conclusion that the individual had possession of the key and an inference that he or she had access to the contents of the strongbox. In fact, in almost any compelled physical act, there will be an inference that can be drawn, which could in some fashion prove incriminating. Yet, the Supreme Court has determined that neither the signing of the consent, the requiring of the handwriting exemplar, the wearing of a blouse, nor the seizing of a key to a strongbox constitute testimonial acts. As explained above, the dividing line the Supreme Court has drawn is whether the suspect is compelled to provide “any knowledge he might have.” Doe, 487 U.S. at 216 (citation omitted). Similarly, the implicit inference that one might draw from the biometric unlock procedure — that the cell phone was at some point accessed in order to program the biometric lock feature — is no different in significance than any of the above inferences. It is of the same scale that existed in Doe, Gilbert and the other cases discussed above. The implicit inference is also not necessarily as firm as on first impression — the Touch ID feature on an iPhone permits up to five fingerprints to be programmed, thus allowing the potential for multiple users to program the feature. As a result, the Court concludes that any implicit inference that can be drawn from a biometric unlock procedure is not of testimonial significance.