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Accessing Google Location History Records Is Not a Search — At Least When Limited — Fourth Circuit Rules

An important case on "The Digital Fourth Amendment"


Regular readers may recall my prior coverage of United States v. Chatrie, a case on the Fourth Amendment implications of collecting Google location history records—location records stored by Google about where logged-in Google users are located—which in the Chatrie case were used to identify a bank robber.  The Fourth Circuit handed down its ruling in the case yesterday, and I thought I would give a quick summary and offer some thoughts.

My 2022 post explained the technology, the facts, and the trial court's ruling, so please go there for the details, as I'd rather not repeat it all here.  (Go ahead, really, I'll wait. Okay, back?  Now let's continue.). As you'll recall from my 2022 post—which you just read, right?— the trial court in this case (1) assumed that collecting the records was a Fourth Amendment search; (2) adopted a very narrow view of how broadly warrants for such records can extend, under which the Chatrie geofence warrant was plainly unconstitutional; and then (3) upheld the collection of records anyway under the good-faith exception to the warrant requirement because it was such a novel issue.  My 2022 post was skeptical of this, suggesting that no search may have occurred in the first place and that warrants should be a lot broader than what the district court concluded.

In the new ruling, the Fourth Circuit rules 2-1 that no search occurred. Judge Jay Richardson wrote the majority opinion, and he was joined by Judge Harvie Wilkinson, Judge James Wynn dissented.  Here's the key reasoning from the majority opinion by Judge Richardson:

Relying on Carpenter, Chatrie argues that the government conducted a search when it obtained his Location History data from Google. We disagree. Carpenter identified two rationales that justify applying the third-party doctrine: the limited degree to which the information sought implicates privacy concerns and the voluntary exposure of that information to third parties. Both rationales apply here. Accordingly, we find that Chatrie did not have a reasonable expectation of privacy in the two hours' worth of Location History data that law enforcement obtained from Google. So the government did not conduct a search by obtaining it.

Start with the nature of the information sought. Carpenter, 585 U.S. at 314, 138 S.Ct. 2206. The government requested and obtained only two hours' worth of Chatrie's Location History data.16 By no means was this an "all-encompassing record of [Chatrie's] whereabouts … provid[ing] an intimate window into [his] person[al] life." Carpenter, 585 U.S. at 311, 138 S.Ct. 2206. All the government had was an "individual trip viewed in isolation," which, standing alone, was not enough to "enable[ ] deductions about 'what [Chatrie] does repeatedly, what he does not do, and what he does ensemble.' "Beautiful Struggle, 2 F.4th at 342 (quoting Maynard, 615 F.3d at 562–63). The information obtained was therefore far less revealing than that obtained in Jones, Carpenter, or Beautiful Struggle and more like the short-term public movements in Knotts, which the Court found were "voluntarily conveyed to anyone who wanted to look." Carpenter, 585 U.S. at 314, 138 S.Ct. 2206 (quoting Knotts, 460 U.S. at 281, 103 S.Ct. 1081). A record of a person's single, brief trip is no more revealing than his bank records or telephone call logs. See Miller, 425 U.S. at 442, 96 S.Ct. 1619; Smith, 442 U.S. at 742, 99 S.Ct. 2577. Chatrie thus did not have a "legitimate 'expectation of privacy,' " in the information obtained by the government, so the first rationale for the third-party doctrine applies here. Carpenter, 585 U.S. at 314, 138 S.Ct. 2206 (quoting Miller, 425 U.S. at 442, 96 S.Ct. 1619).

Furthermore, Chatrie voluntarily exposed his location information to Google by opting in to Location History. Id. at 315, 138 S.Ct. 2206. Consider again how Location History works. Location History is an optional setting that adds extra features, like traffic updates and targeted advertisements, to a user's experience. But it is "off by default" and must be affirmatively activated by a user before Google begins tracking and storing his location data. J.A. 1333–34. Of course, once Google secures this consent, it monitors his location at all times and across all devices. Yet even then, Google still affords the user ultimate control over how his data is used: If he changes his mind, he can review, edit, or delete the collected information and stop Google from collecting more. Whether Google tracks a user's location, therefore, is entirely up to the user himself. If Google compiles a record of his whereabouts, it is only because he has authorized Google to do so.

Nor is a user's consent secured in ignorance, either. See Carpenter, 585 U.S. at 314, 138 S.Ct. 2206 (explaining that the third-party doctrine applies to information "knowingly shared with another"). To the contrary, the record shows that Google provides users with ample notice about the nature of this setting. Before Google allows a user to enable Location History, it first displays text that explains the basics of the service. The text states that enabling Location History "[s]aves where you go with your devices," meaning "[t]his data may be saved and used in any Google service where you were signed in to give you more personalized experiences." It also informs a user about his ability to view, delete, or change his location data. A user cannot opt in to Location History without seeing this text.

So unlike with CSLI, a user knowingly and voluntarily exposes his Location History data to Google. First, Location History is not " 'such a pervasive and insistent part of daily life' that [activating it] is indispensable to participation in modern society." Carpenter, 585 U.S. at 315, 138 S.Ct. 2206 (quoting Riley, 573 U.S. at 385, 134 S.Ct. 2473). Carpenter found that it is impossible to participate in modern life without a cell phone. Id. But the same cannot be said of Location History. While Location History offers a few useful features to a user's experience, its activation is unnecessary to use a phone or even to use apps like Google Maps. Chatrie gives us no reason to think that these added features are somehow indispensable to participation in modern society and that his decision to opt in was therefore involuntary. That two-thirds of active Google users have not enabled Location History is strong evidence to the contrary. Cf. Riley, 573 U.S. at 385, 134 S.Ct. 2473 (noting that, as of 2014, "a significant majority of American adults" owned smartphones). Thus, a user can decline to use Location History and still participate meaningfully in modern society.

Second, unlike CSLI, Location History data is obtained by a user's affirmative act. Carpenter noted that "a cell phone logs a cell-site record by dint of its operation, without any affirmative act on the part of the user beyond powering up." 585 U.S. at 315, 138 S.Ct. 2206. But Location History is off by default and can be enabled only by a user's affirmative act. A person need not go off the grid by "disconnecting [his] phone from the network … to avoid" generating Location History data; instead, he can simply decline to opt in and continue using his phone as before. See id. Thus, "in [every] meaningful sense," a user who enables Location History "voluntarily 'assume[s] the risk' " of turning over his location information. Id. (quoting Smith, 442 U.S. at 745, 99 S.Ct. 2577). So the second rationale for the third-party doctrine applies here, too. The third-party doctrine therefore squarely governs this case. The government obtained only two hours' worth of Chatrie's location information, which could not reveal the privacies of his life. And Chatrie opted in to Location History on July 9, 2018. This means that he knowingly and voluntarily chose to allow Google to collect and store his location information. In so doing, he "t[ook] the risk, in revealing his affairs to [Google], that the information [would] be conveyed by [Google] to the Government." Miller, 425 U.S. at 443, 96 S.Ct. 1619. He cannot now claim to have had a reasonable expectation of privacy in this information. See Smith, 442 U.S. at 743–44, 99 S.Ct. 2577. The government therefore did not conduct a search when it obtained the data.

I think this is the correct analysis.  Indeed, it's what I argue for in my forthcoming book, The Digital Fourth Amendment, where I discuss what was then the pending Chatrie case. (I'm told that I'll be to add a quick update to the manuscript to include the new ruling.)

According to Judge Richardson, this does not mean that access to Google location history records is categorically outside the Fourth Amendment.  That is true because Fourth Circuit precedent has adopted the so-called mosaic theory, the idea that whether and when Carpenter kicks in and calls data collection a search depends on how much data collection has occurred.  This warrant asked for only a brief period of records, just a two-hour span, and the majority concludes that was not enough to trigger a mosaic:

Although not couched under this label, Beautiful Struggle articulated a version of what one scholar calls the "Mosaic Theory" of the Fourth Amendment. See Orin S. Kerr, The Mosaic Theory of the Fourth Amendment, 111 Mich. L. Rev. 311 (2012). The Mosaic Theory asks whether the government has observed enough of a person's physical movements to deduce intimate details about his private life that could not be learned from simply observing his isolated trips or activities. Under this theory, access to a person's short-term movements does not invade his reasonable expectation of privacy. Such information reveals only the locations he visits and nothing more, which is something that law enforcement could learn from traditional means of surveillance anyway. Beautiful Struggle, 2 F.4th at 341; Jones, 565 U.S. at 429, 132 S.Ct. 945 (opinion of Alito, J.). But much more is revealed when the government accesses a larger swath of a person's movements, as this "enables deductions about 'what a person does repeatedly, what he does not do, and what he does ensemble,' which 'reveal[s] more about a person than does any individual trip viewed in isolation.' " Beautiful Struggle, 2 F.4th at 342 (alteration in original) (quoting Maynard, 615 F.3d at 562–63)). In other words, it exposes "not only his particular movements, but through them his 'familial, political, professional, religious, and sexual associations.' " Carpenter, 585 U.S. at 311, 138 S.Ct. 2206 (quoting Jones, 565 U.S. at 415, 132 S.Ct. 945 (opinion of Sotomayor, J.)). Society does not expect that law enforcement would or could gather such a wealth of intimate details about an individual's personal life from his physical movements. Jones, 565 U.S. at 430, 132 S.Ct. 945 (opinion of Alito, J.). So when the government crosses that line, it invades a person's reasonable expectation of privacy and conducts a search.

The dissent misses Beautiful Struggle's distinction when it catalogues the kind of private details that could be learned from two hours' worth of Location History. According to the dissent, a two-hour snippet of Location History could reveal a wealth of otherwise unknowable and intimate information, like a person's "romantic rendezvous," "medical appointments," or "afternoon and early-evening routines." Diss. Op. at ––––. But the theory adopted in Beautiful Struggle rejects this exact proposition. To be sure, a two-hour snippet might show that someone visited an apartment, swung by a doctor's office, and then popped into a gym. Yet glimpsing this single trip in isolation could not itself enable sound deductions about that person's habits, routines, and associations. For example, he may have visited the apartment because he is having an affair, but he equally could have been seeing a friend for coffee, touring a housing upgrade, or buying a couch off of Facebook marketplace. Similarly, he might have visited the doctor's office for his appointment, yet he also could have been dropping off his spouse or collecting information about the doctor's services or needs. And observing someone enter a gym once certainly cannot confirm whether he is a gym rat or simply riding a New Years high. Only by observing that person's movements over a longer period could the police reliably deduce his habits, routines, and associations. No such deductions could accurately be made from a mere two-hour glimpse.

Applying this theory here leads to a straightforward conclusion. As the dissent correctly observes, Location History has capabilities much like GPS data and CSLI. But unlike in Carpenter or Jones, the government in this case obtained only two hours' worth of Chatrie's Location History data. Although this brief glimpse into his whereabouts may have revealed the locations he visited, it was plainly insufficient to offer insight into his habits, routines, and associations. So the government did not invade his "legitimate 'expectation of privacy' " by obtaining it.Carpenter, 585 U.S. at 314, 138 S.Ct. 2206 (quoting Miller, 425 U.S. at 442, 96 S.Ct. 1619).

Judge Wynn dissented, arguing that Carpenter can be best understood as creating a multi-factor analysis for what is a search that looks to underlying shifts of government power:

Leading scholars agree that Carpenter created a factor-based test derived from those considerations, though they disagree on which factors are the most important or mandatory. E.g., Paul Ohm, The Many Revolutions of Carpenter, 32 Harv. J.L. & Tech. 357, 363, 369 (2019) (recognizing Carpenter created "new, multi-factor test" to analyze an individual's reasonable privacy expectation against intruding technology and "herald[ed] a new mode of Constitutional analysis"); Susan Freiwald & Stephen W. Smith, The Carpenter Chronicle: A Near-Perfect Surveillance, 132 Harv. L. Rev. 205, 219 (2018) (multifactor analysis was "clearly central" to the Court's holding); Tokson, The Aftermath of Carpenter, supra, at 1830 (describing the "Carpenter factors" and concluding from a survey of cases that "[a] multifactor Carpenter test has begun to emerge from the lower court[s]").

In reaching this conclusion, scholars rely on the Court's analysis and its concluding sentence, which reads: "In light of the deeply revealing nature of CSLI, its depth, breadth, and comprehensive reach, and the inescapable and automatic nature of its collection, the fact that such information is gathered by a third party does not make it any less deserving of Fourth Amendment protection." Carpenter, 585 U.S. at 320, 138 S.Ct. 2206.

In my view, such a factor-based examination is the correct interpretation of the Court's opinion. Again, central to the Court's analysis was one overarching principle: the need to maintain historical Fourth Amendment protections against expanding police surveillance capabilities. Throughout its analysis, Carpenter extensively emphasized that the government historically could not conduct intrusions as comprehensive, retrospective, intimate, and efficient as those made possible by technological advancements like CSLI. See, e.g., id. at 304–05, 138 S.Ct. 2206 (stating the Fourth Amendment analysis with respect to digital data must be "informed by historical understandings" of reasonable searches (quotations omitted)); id. at 305, 138 S.Ct. 2206 (discussing historical expectations); id. at 312, 138 S.Ct. 2206 (retrospective information was traditionally "unknowable"); id. at 320, 138 S.Ct. 2206 (stating that the police's use of CSLI infringed upon the Framers' intent in enacting the Fourth Amendment).

This rationale reflects the Court's understanding that rapid technological advances have created shifts "in kind and not merely in degree from the technology of the past." Ohm, supra, at 399. These shifts required the Court to adjust its analysis of the Fourth Amendment to "preserv[e the] degree of privacy … that existed when the Fourth Amendment was adopted," as it has with technological changes in the past. Carpenter, 585 U.S. at 305, 138 S.Ct. 2206 (quoting Kyllo, 533 U.S. at 34, 121 S.Ct. 2038); see id. at 305–06, 138 S.Ct. 2206 (describing this philosophy in the Court's Fourth Amendment jurisprudence and citing cases); id. at 318, 138 S.Ct. 2206 ("When confronting new concerns wrought by digital technology, this Court has been careful not to uncritically extend existing precedents."); see also Orin S. Kerr, The Digital Fourth Amendment: Implementing Carpenter 10, 16–19 (USC Law Legal Studies Paper No. 18-29) (describing this phenomenon in the Court's jurisprudence as an "equilibrium-adjustment"); Denae Kassotis, The Fourth Amendment and Technological Exceptionalism After Carpenter: A Case Study on Hash-Value Matching, 29 Fordham Intell. Prop. Media & Ent. L.J. 1243, 1302 (2019) (explaining that Riley and Carpenter reflect the Court's understanding of the exceptional nature of technology and adaptation of the law to protect privacy).

Put simply, the Court declined to extend existing doctrines to exempt CSLI from Fourth Amendment protections based on the principle that it first recognized decades earlier: previously unimaginable technology that reveals unprecedented amounts of personal information requires new rules. Carpenter, 585 U.S. at 310–14, 138 S.Ct. 2206 (citing the Jones concurrences and rejecting the "mechanical" application of old doctrines); accord Riley, 573 U.S. at 393, 134 S.Ct. 2473 (stating that comparing a physical search to a cell phone search is like "saying a ride on horseback is materially indistinguishable from a flight to the moon"). Thus, "[t]he beating heart" of Carpenter "is its deep and abiding belief in the exceptional nature of the modern technological era." Ohm, supra, at 399.

By that standard, Judge Wynn argues, a search occurred: "A faithful reading of Carpenter—not to mention common sense—compels the conclusion that when the police obtained Chatrie's Location History data, they engaged in a Fourth Amendment search. That conclusion is evident upon evaluating how the Carpenter factors apply to the Location History intrusion in this case."

So what does this new decision mean?  How important is it going forward?

I think Chatrie is medium-important.  Its importance lies in it being a key reminder that not all location data is protected under the Fourth Amendment after Carpenter.  As I wrote back in 2022, it was puzzling that a lot of lower courts did not want to address this; they wanted to jump straight to how broad warrants could extend over these kind of records.  Chatrie is a key reminder that there's an earlier step.  The collection of location records may not be a search at all.

At the same time, Chatrie's practical importance is undercut greatly by Google's announcement, almost immediately after the Chatrie oral argument, that it is going to phase out Google-stored location history records.  Just based on the public record, it appears that Google was following the argument closely.  My guess is that, upon seeing that the panel might rule that no search occurs in these cases, Google decided to eliminate its own possession of those records so governments could not compel them from Google without a warrant.

Whether that was the goal, that is the effect.  And it means that the panel's ruling likely won't have a major impact going forward.  Granted, I'd guess that Google or other providers will have other location records that the government might be able to compel in the future.  But iI would guess those records won't be the kind of clear opt-in records that Location History records are, which means that collecting them is more likely to be a search.  And if that's right, subsequent particularly question of how broadly the search can go under a warrant remains, and it will be critical then.

Finally, note that the split over whether the Fourth Amendment recognizes a "mosaic theory" at all lives on. As I have argued (and as the majority generously noted), I don't think the theory is coherent or workable.  Twelve years after I first made that argument, lower courts are pretty divided on the question.  Some courts have adopted the mosaic, while others reject it on workability grounds.  The Supreme Court is on a long holiday from search and seizure law right now.  But if the Justices should some day wish to address some of the lower court disagreement on what the Fourth Amendment means, whether to recognize the mosaic theory will be an important question for the Court to answer.