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Smartphones, Contents of the Mind, and the Fifth Amendment

Smartphones, Contents of the Mind, and the Fifth Amendment, illustrative photo

Credit: Andrij Borys Associates, Shutterstock

"Papers are the owner's goods and chattels; they are his dearest property, and are so far from enduring a seizure, that they will hardly bear an inspection ..."

—Lord Camden, Entick v. Carrington (1765)

"I write separately, however, just to make explicit what is implicit in the analysis of that opinion: that the Fifth Amendment provides absolutely no protection for the contents of private papers of any kind."

—Justice O'Connor, United States v. Doe (1984)

Smartphones are both ubiquitous—more than two billion are in use throughout the world today—and they collect a vast amount of personal data.8 A great deal of attention has been placed on the data itself, with the 2015 Apple/FBI confrontation providing a prominent example. The FBI obtained an iPhone that had been used by one of the terrorists killed in the December 2015 attack in San Bernardino, CA.9 The FBI requested an order from the U.S. District Court for the Central District of California directing Apple to create and provide an operating system that would bypass the phone's defenses, giving the FBI far easier access to whatever data remained on the phone. The denouement of this court confrontation would have been interesting—the FBI's reliance on the 1789 All Writs Act could have had far-reaching consequencesa—but in the end the FBI apparently obtained access to the iPhone's data through other means. This case is but one of hundreds that points to the importance of smartphones in our everyday lives and, perhaps more importantly, to the ability of smartphones to record the details of those lives.

This Viewpoint suggests the data-centric focus ignores an equally important issue: the nature of the relationship between smartphones and their users. I begin with a brief review of the erosion in the belief in a mind-body separation and a growing recognition that the boundaries between the individual and the "outside" world are far more tenuous than once thought. As a result, interrelated strands of philosophy, artificial intelligence, and psychology now point to the conclusion that the smartphone, as used, is more an extension of the user's mind than simply a useful artifact. This raises a host of issues that suggest a reconsideration of the smartphone's legal status, or at least motivates additional protective measures for the user.

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An Extension of the Self

I begin with a brief comparison of the differing approaches to cognition attributed to René Descartes and Martin Heidegger. In Meditations on First Philosophy (1641), Descartes asserted that the mind is a non-physical, non-spatial substance that is separate and distinct from the world of physical objects, a world that includes our bodies. Given this distinction, mind, cognition, and intelligence are explained in terms of "internal" representation and computation. Put simply, external objects cause sensations in the thinker's mind, which in turn cause perceptions that are arranged into representations of the outside world. When the thinking thing thinks about the outside world, it performs computations on these internal representations.

In his 1922 work, Being and Time, Martin Heidegger threw out Descartes' mind-body distinction. According to Heidegger, the fundamental basis for human existence is our "being in the world," something Heidegger called dasein. With dasein, interaction with the world takes precedence over detached contemplation, and internal representations become an unnecessary hypothesis.

In his Phenomenology of Perception Maurice Merleau-Ponty extended Heidegger's approach into a theory of embodied relations.6 When one develops the skill of handling an object, the object is incorporated into one's bodily framework, or "schema." Merleau-Ponty gave several examples, including that of the skilled typist and his typewriter (though the example is dated, it is easily adapted for the 21st century). Using the language of cognitive extension—incorporating the typewriter keys into the self—he described in the following way how the typist interacts with the typewriter: "When the typist performs the necessary movements on the typewriter, these movements are governed by an intention, but the intention does not posit the keys as objective locations. It is literally true that the subject who learns to type incorporates the keybank space into his bodily space."6

For purposes of this Viewpoint, I will loosely group Heidegger and Merleau-Ponty under the heading of phenomenology. The distinction between the Cartesian and the phenomenological approaches to the mind can be seen in the differing emphases of AI research programs. Many early AI experiments adopted a Cartesian approach, establishing internal (code space) representations and then performing simple tasks through computations on those representations. These early experiments quickly ran into the frame problem: If the state of the world changes, how is a programmed entity to determine which elements of its internal representation have changed, and which have stayed the same? Early AI researchers sought to mitigate the frame problem by drastically constraining the scope of their artificial worlds. While this approach often lead to interesting results, it made it extremely difficult to model everyday interaction with any precision.

More recent AI researchers such as Rodney Brooks and Lucy Suchman have avoided the frame problem by eschewing internal representations and modeling cognition in the context of "situated action."2,7 This non-representational approach to AI has connections to several generations of cognitive psychologists who have questioned the Cartesian model and pursued an extended, interactive approach to cognition. In 1904, William James published a paper entitled "Does 'Consciousness' Exist?" in which he challenged the existence of a mind that contains representations of an external world.4 James claimed we perceive the world "directly," as opposed to through the mediation of internal representations. James Gibson extended this approach in his Ecological Approach to Visual Perception.3 Expressly echoing the work of Merleau-Ponty, Gibson suggested that our perception is direct and not supplemented through mental representations. He further characterized our interaction with the world in terms of "affordances"—opportunities, or invitations to action. More recent work in extended cognition has used dynamical systems theory to capture Gibson's ideas, modeling cognition in terms of the state-space evolution of dynamical systems that include both the person and the immediate objects of her surroundings.5

Phenomenology, AI, and extended cognition thus suggest that when we interact with "external" objects such as our smartphones, cognition is taking place in a system that includes both our persons and the phone. But we can actually take this a step further: it is not just that the smartphone is part of the thinking thing, as it were, but that we actually offload cognitive functions from our (internal) selves onto the phone. This is not as unusual as one might think. Many of us use notes when teaching a class rather than relying on internal memory, much to the benefit of all involved. In their 2015 article, "The Brain in Your Pocket: Evidence that Smartphones are Used to Supplant Thinking,"1 Barr et al. explored the notion of "cognitive miserliness"—the idea that humans are prone to avoiding costly analytic thought in favor of simple heuristics and mental shortcuts. Barr et al. demonstrated through a series of experiments that some people actually offload cognitive tasks onto their smartphones. The ability of a smartphone to accept such offloading distinguishes it from most objects encountered in everyday experience.

The smartphone, as used, is more an extension of the user's mind than simply a useful artifact.

One might expect that the smartphone's role in cognition has been incorporated into legal thinking, with various courts recognizing the uniquely personal nature of the smartphone within the context of Fourth Amendment prohibitions against illegal search and seizure and Fifth Amendment prohibitions against compulsory self-incrimination. In particular, one might think that Fifth Amendment prohibitions against the compulsory disclosure of the "contents of the mind"b might now be tied to the cognitive aspects of smartphone use. One would be wrong. As I will discuss here, the law has been moving in precisely the opposite direction for a very long time.

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The Fifth Amendment and Private Papers: Entick to Fisher

To highlight the trajectory of the law, I will use personal papers as an analogous personal tool; I begin with Entick v. Carrington,c a prominent case in English Common Law that dates back to 1765. In this case one John Entick sued four Messengers of the King for entering his home and seizing his personal papers and books. The presiding judge, Lord Camden, came down firmly on Entick's side. Lord Camden highlighted the special nature of personal papers, stating that not only was their seizure improper, but they should not have even been inspected: "Papers are the owner's goods and chattels; they are his dearest property, and are so far from enduring a seizure, that they will hardly bear an inspection; and though the eye cannot by the laws of England be guilty of a trespass, yet where private papers are removed and carried away the secret nature of those goods will be an aggravation of the trespass, and demand more considerable damages in that respect."—Entick v. Carrington (1765); emphasis added

The United States Supreme Court closely followed the Entick case in its Boyd v. United States (1886) decision, quoting it extensively.d In this case, the E.A. Boyd and Sons firm had run afoul of the 1874 Customs Act, an act that made it illegal to import goods without paying the appropriate duties. It provided for penalties that included substantial fines, possible jail terms, and the forfeiture of goods. The 1874 Act also included a clause that gave real teeth to any government document request:

"[I]f the defendant or claimants shall fail or refuse to produce such book, invoice, or paper in obedience to such notice, the allegations stated in the said motion shall be taken as confessed, unless his failure or refusal to produce the same shall be explained to the satisfaction of the court."

In short, if one did not provide the papers requested by the government, one was assumed to be guilty of whatever crime the government was attempting to prove. Boyd and Sons were compelled to produce papers that were used to incriminate them. They argued that this was compelled self-incrimination, and thus "unconstitutional and void." A unanimous Supreme Court agreed with the Boyds, issuing a far-reaching ruling that placed personal papers beyond the reach of law enforcement. The Boyd Court quoted the Entick decision at length to make three important points:

  1. Personal papers are a form of private property that is particularly precious to its owner;
  2. There is no precedent in English law for the seizure of personal papers; and
  3. The drafters of the Fourth and Fifth amendments were aware of the Entick decision, so arguments based on original intent must account for the priority of personal papers stressed in Entick.

The Boyd Court concluded that when it comes to the seizure of private papers, "the Fourth and Fifth Amendments run almost into each other": "[W] have been unable to perceive that the seizure of a man's private books and papers to be used in evidence against him is substantially different from compelling him to be a witness against himself."

The Boyd precedent lasted for almost 100 years, but after slow and steady erosion it finally came to an end in 1976 with Fisher v. United States.e In Fisher, the Court found that when a defendant is required to surrender documents held by a third party, "no constitutional rights are touched. The question is not of testimony, but of surrender." In his dissent, Justice Brennan lamented a lost right and, perhaps unknowingly, summarized a great deal of research in a variety of fields: "An individual's books and papers are generally little more than an extension of his person. They reveal no less than he could reveal upon being questioned directly."—Justice Brennan, Fisher v. United States (1976)

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Protecting the User

We have seen that for at least 100 years, British and American law held that personal papers were not subject to search and seizure. To this day Fifth Amendment law forbids the compelled production of the contents of a defendant's mind. Recent research into extended cognition suggests that the contents of our minds may include data on our smartphones—the modern analogue of personal papers—and yet the law allows the seizure of smartphones under a wide variety of circumstances. There appears to be a contradiction: Is there a technical or legal resolution?

The technical path seems clear. Just as an 18th-century statesman might choose to keep his personal papers in a safe, smartphones can be adapted to back up selected data to privately held cryptographic vaults. The "private" element is important, as the third-party doctrine maintains that a user has no reasonable expectation of privacy in anything given to a third party. Established in the 1976 case United States v. Millerf and applied to telephony in Smith v. Marylandg in 1979, the doctrine predates cellular technology (1983), the World Wide Web (1990), and commercial access to the Internet (1995). Clearly the nature of the data individuals provide to third parties has changed radically since the Miller and Smith cases were decided.

There has been some progress in this area. In a concurring opinion in U.S. v. Jonesh Justice Sotomayor expressed concern regarding the amount and revelatory nature of data provided to third parties in the "digital age": "More fundamentally, it may be necessary to reconsider the premise that an individual has no reasonable expectation of privacy in information voluntarily disclosed to third parties. E.g., Smith, 442 U. S., at 742; United States v. Miller, 425 U. S. 435, 443 (1976). This approach is ill-suited to the digital age, in which people reveal a great deal of information about themselves to third parties in the course of carrying out mundane tasks. People disclose the phone numbers that they dial or text to their cellular providers; the URLs that they visit and the email addresses with which they correspond to their Internet service providers; and the books, groceries, and medications they purchase to online retailers."—Justice Sotomayor, United States v. Jones

In Carpenter v. U.S. the question of whether cellular location data should be made available to law enforcement without a warrant is now squarely before the U.S. Supreme Court. The Court has an opportunity to recognize the unique nature of cellular handsets and to provide at least of modicum of protection to the user.

From this author's lay perspective, it would seem there are further legal alternatives. At one extreme courts may grant the individual immunity from prosecution based solely on any information found on his or her smartphone. My friends who are prosecutors may howl in rage, but note that this extreme step still allows for the collection of data that may be used to track down co-conspirators. At the other extreme, we may continue to treat smartphones as we would any other piece of personal physical evidence, such as fingerprints or blood samples. Such an approach ignores the cognitive aspect of the smartphone, and leaves the law in clear tension with technology and human psychology.

Smartphones have become part and parcel of our everyday lives and an extension of our thinking selves.

There is room between these two extremes, room that might include special warrants for smartphone data that require a showing of probable cause that a specific crime within a predefined class has been committed, and that specifies the information to which law enforcement is entitled. The "super warrants" required for wiretaps have similar requirements, though wiretaps provide less information than is commonly stored in a smartphone.

All law involves striking balances. Just as our right to free speech does not extend to falsely shouting "fire" in a crowded theatre, so law enforcement may not enjoy the benefits of an illegal search. So it should be here. Smartphones have become part and parcel of our everyday lives and an extension of our thinking selves. We should be able to enjoy this technology with at least some recognition that the contents of our minds may be found outside of our physical selves.

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1. Barr, N. et al. The brain in your pocket: Evidence that smartphones are used to supplant thinking. Computers in Human Behavior 48 (July 2015), 473–480.

2. Brooks, R. Intelligence without representation. Artificial Intelligence 47, 1–3 (Jan. 1991), 139–159.

3. Gibson, J. Ecological Approach to Visual Perception. Houghton Mifflin, 1979.

4. James, W. Does 'consciousness' exist? Journal of Philosophy, Psychology, and Scientific Methods 1, (1904), 477–491.

5. Käufer, S. and Chemero, A. Phenomenology: An Introduction. Polity Press, Cambridge, 2015.

6. Merleau-Ponty, M. Phenomenology of Perception. C. Smith (trans.). Routledge, New York and London. Originally published in French as Phénoménologie de la Perception (1962/1945).

7. Suchman, L. Plans and Situated Actions: The Problem of Human-Machine Communication (Learning in Doing: Social, Cognitive and Computational Perspectives). Cambridge University Press, 1987.

8. Wicker, S.B. Cellular Convergence and the Death of Privacy. Oxford University Press, 2013.

9. Wu, F. No easy answers in the fight over iPhone decryption. Commun. ACM 59, 9 (Sept. 2016), 20–22.

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Stephen Wicker ([email protected]) is a professor of Electrical and Computer Engineering at Cornell University and a Fellow of the IEEE.

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a. An overview of the case can be found at An amicus brief filed by 32 law professors provides more detail regarding the applicability of the All Writs Act (see "Amicus Curiae Brief Of Law Professors In Support Of Apple," Case No. 5:16-CM-00010-SP).

b. Curcio v. United States, 354 U.S. 118 (1957).

c. Entick v. Carrington, 19 Howell's State Trials 1029 (1765).

d. Boyd v. United States, 116 U.S. 616 (1886).

e. Fisher v. United States, 425 U.S. 391 (1976).

f. United States v. Miller, 425 U.S. 435 (1976).

g. Smith v. Maryland, 442 U.S. 735 (1979).

h. United States v. Jones, 132 U.S. 945 (2012).

The author gratefully acknowledges the comments of the reviewers—they have made this a much better Viewpoint. The author also gratefully acknowledges the comments, editing, and general support of Sarah Wicker.

This work was funded, in part, by the NSF TRUST Science and Technology Center.

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