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Important Fourth Circuit Ruling on Cell Phone Border Searches

The court requires some level of cause and also adds a nexus requirement.


The Fourth Circuit handed down a significant ruling today in United States v. Kolsuz on how the Fourth Amendment applies to cell phone searches of cell phones seized at the border. Although the court ultimately affirmed the conviction based on the good-faith exception, the court also introduced a new and significant limit on border searches. Judge Pamela Harris penned the majority opinion, and Judge Wilkinson added a concurrence. There's a lot going on in the opinion, and it merits a close read, but I'll try to offer some highlights and commentary here.

I. An Overview of the Caselaw

A recap of the doctrine here may be helpful. Traditionally, searches at the border don't require any suspicion on the theory that the government has a strong sovereign interest in regulating what enters and exits the country. But there is caselaw indicating that some border searches are so invasive that they do require some kind of suspicion. When the courts first applied the Fourth Amendment to border searches of computers, they held that searches of computers were ordinary searches that required no suspicion. This was the view of the Fourth Circuit in United States v. Ickes, a 2005 opinion by Judge Wilkinson.

Enter the Ninth Circuit, in a 2013 case called United States v. Cotterman, which held that a computer search from a computer seized at the border requires reasonable suspicion if it is a "forensic" search but not if it is a "manual" search. The old cases allowing searches without any cause involved an officer just poking through the computer using its operating system, the Ninth Circuit reasoned, and searches of computers using forensic equipment produce more invasive searches and should require reasonable suspicion.

In 2014, the Supreme Court decided Riley v. California. Riley held that a warrant is required to search a cell phone incident to arrest because of the quantity and nature of information on a cell phone. That created what amounts to a digital-only rule: No warrant is required to search incident to arrest for physical items, but a warrant is required for a search of digital items. After Riley, defendants started saying that maybe the rule for border searches shouldn't only be Cotterman but Riley. That is, maybe there shouldn't be any border search exception at all for computer searches, and all computer searches (or at least forensic ones) should require a warrant.

In March, in United States v. Molini-Isidoro, the Fifth Circuit declined to reach the issue on the ground that the good faith exception applied either way. And last month, in United States v. Vergara, the Eleventh Circuit rejected the view that forensic searches at the border should require a warrant or probable cause. The Eleventh Circuit didn't take a view on whether reasonable suspicion was required, however, as the defendant hadn't challenged that issue.

II. The New Case, United States v. Kolsuz

In the new case, Kolsuz, the Fourth Circuit agrees with the Ninth Circuit that at least some suspicion is required for a forensic search of a cell phone seized at the border. The Fourth Circuit roots this holding in Riley, and the concerns that Riley embraced that had also driven Cotterman. It leads to this result (with footnotes added into main text and paragraph breaks added for easier blog reading):

After Riley, we think it is clear that a forensic search of a digital phone must be treated as a nonroutine border search, requiring some form of individualized suspicion. See Kolsuz, 185 F. Supp. 3d at 858; see also United States v. Saboonchi, 48 F. Supp. 3d 815, 819 (D. Md. 2014) ("Saboonchi II") (discussing ways in which Riley confirms prior holding that border searches of digital devices are nonroutine). Indeed, the impact of Riley is plain enough that the government's brief does not seriously contest this point, focusing instead on the argument (which we next address) that nonroutine or not, the search of Kolsuz's phone was justified under the border exception.

[FN5:The government does note that in Ickes, 393 F.3d at 505–07, our court treated a search of a computer as a routine border search, requiring no individualized suspicion for the search. But as the district court explained, Ickes approved a manual, on-site inspection of computer contents that would be accessible to any user, and did not address the use of the sophisticated forensic search methods at issue here. Kolsuz, 185 F. Supp. 3d at 853–54; see also Saboonchi, 990 F. Supp. 2d at 546 (distinguishing Ickes on same ground). Because Kolsuz does not challenge the initial manual search of his phone at Dulles, we have no occasion here to consider whether Riley calls into question the permissibility of suspicionless manual searches of digital devices at the border.]

We also note that shortly after argument in this case, the Department of Homeland Security adopted a policy that treats forensic searches of digital devices as nonroutine border searches, insofar as such searches now may be conducted only with reasonable suspicion of activity that violates the customs laws or in cases raising national security concerns. U.S. Customs and Border Prot., CBP Directive No. 3340-049A, Border Search of Electronic Devices 5 (2018). That the agency has chosen to adopt these requirements, of course, does not establish that they are constitutionally mandated. Cf. Ickes, 393 F.3d at 507 (distinguishing between agency practice and constitutional requirements).

But it does suggest, as courts have anticipated, that the distinction between manual and forensic searches is a perfectly manageable one, see Cotterman, 709 F.3d at 967 (categorizing forensic searches as nonroutine requires only "that officers make a commonsense differentiation between a manual review of files on an electronic device and application of computer software to analyze a hard drive"), and that treating forensic phone searches as nonroutine need not interfere unduly with the agency's protective mission at the border, see Saboonchi, 990 F. Supp. 2d at 570.

[FN6:The new policy does not use the "routine" and "nonroutine" terminology of Supreme Court case law, distinguishing instead between "basic" and "advanced" searches. But the import is the same. "Basic" searches (like those we term "manual") are examinations of an electronic device that do not entail the use of external equipment or software and may be conducted without suspicion. "Advanced" searches (like "forensic" searches) involve the connection of external equipment to a device – such as the Cellebrite Physical Analyzer used on Kolsuz's phone – in order to review, copy, or analyze its contents, and are subject to the restrictions noted above. See U.S. Customs and Border Prot., CBP Directive No. 3340-049A, Border Search of Electronic Devices 4– 5 (2018); Molina-Isidoro, 884 F.3d at 294 & n.2 (Costa, J., concurring).]

This is important for three reasons. First, the Fourth Circuit requires suspicion for forensic searches of cell phones seized at the border. Second, it clarifies significantly the forensic/manual distinction, which has always been pretty uncertain to me. Third, it leaves open that some suspicion may be required for manual searches, too.

The Fourth Circuit ultimately does not rule on whether the cause required should be reasonable suspicion (as the Ninth Circuit held in Cotterman) or whether it should be a higher standard or a full warrant. This need not be reached because the good faith exception applies either way:

[E]ven if a search is judged to be constitutionally flawed in some way, its fruits need not be suppressed if the agents acted "in reasonable reliance on binding precedent." Davis v. United States, 564 U.S. 229, 241 (2011); see United States v. Baker, 719 F.3d 313, 320–21 (4th Cir. 2013) (describing Davis). In such circumstances, suppression can do little to deter police misconduct, and the "social costs" of suppression – the exclusion from trial of reliable evidence bearing on guilt or innocence – outweigh any deterrence benefits. Davis, 564 U.S. at 237–38.

At the time the CBP officers conducted their forensic search of Kolsuz's phone, there was at least some case law indicating that reasonable suspicion might be required. See Kolsuz, 185 F. Supp. 3d at 855–58 (discussing cases). But there was no case suggesting that even more would be necessary – for a forensic search of a phone at the border or, indeed, for any border search, no matter how nonroutine or invasive. And that remains the case today: Even as Riley has become familiar law, there are no cases requiring more than reasonable suspicion for forensic cell phone searches at the border. But see Vergara, 884 F.3d at 1313–19 (Pryor, J., dissenting) (after Riley, forensic search of phone is not subject to border search exception and therefore requires warrant based on probable cause).

Under these circumstances, we think it was reasonable for the CBP officers who conducted the forensic analysis of Kolsuz's phone to rely on the established and uniform body of precedent allowing warrantless border searches of digital devices that are based on at least reasonable suspicion. See Molina-Isidoro, 884 F.3d at 293 (applying goodfaith exception to warrantless manual search of phone at border). Under Davis's "good-faith" exception to the Fourth Amendment exclusionary rule, that reasonable reliance by itself is enough to bar suppression of the evidence generated by the search. See Baker, 719 F.3d at 321. Accordingly, we need not – and will not – reach the issue of whether more than reasonable suspicion is required for a search of this nature in affirming the judgment of the district court.

At this point I have a quirky personal reaction of wanting to cry, as this is yet another case in which an important legal issue goes undecided because of Davis. That's a case that (as regular readers may remember) I argued and lost at the Supreme Court. I seem doomed to keep enountering Davis to remind me of that unhappy experience. (Number of cases on Westlaw that cite Davis since it was decided in 2011: 1,241.) But putting my personal angst aside, the standard of suspicion goes undecided.

III. The Nexus Requirement

But wait, that's not all. In fact, I don't think it's the most important part of the opinion. The most important part of the opinion comes in a different section, where the Fourth Circuit adds what seems to be a new and important limit on the border search exception: a case-by-case nexus requirement to the government interests that justify the border search exception.

Here's the context. Kolsuz tried to argue that the circumstances in which his phone was searched took the case outside the border search exception entirely. As the opinion explains:

Hamza Kolsuz was detained at Washington Dulles International Airport while attempting to board a flight to Turkey because federal customs agents found firearms parts in his luggage. After arresting Kolsuz, the agents took possession of his smartphone and subjected it to a month-long, off-site forensic analysis, yielding a nearly 900-page report cataloguing the phone's data.

Kolsuz then argued that these circumstances took his case outside the border search exception. As the opinion explains:

In its strongest form, Kolsuz's argument combines all of these factors – his arrest as he sought to depart the country, the phone in government custody miles from the border, the month-long gap between the action at the airport and the end of the search – and argues that taken together, they show that the search in this case is entirely "untethered" from any justification behind the border exception. The rationale allowing outgoing border searches, as Kolsuz describes it, is limited to intercepting contraband as it crosses the national border. Here, with the phone as well as the firearms parts seized by the government and Kolsuz under arrest, there was no contraband poised to exit the country and thus no nexus to that rationale. When that is the case, Kolsuz argues, the border search exception does not apply, because the concerns underlying a warrant exception "define the boundaries of the exception." See Gant, 566 U.S. at 339.

The Fourth Circuit responds with this fascinating passage:

Kolsuz's foundational premise is correct: As a general rule, the scope of a warrant exception should be defined by its justifications. See Riley, 134 S. Ct. at 2484–88 (asking whether "application of the search incident to arrest doctrine to this particular category of effects would untether the rule from the justifications underlying the [search incident to arrest] exception"). As a result, where the government interests underlying a Fourth Amendment exception are not implicated by a certain type of search, and where the individual's privacy interests outweigh any ancillary governmental interests, the government must obtain a warrant based on probable cause. See id. At some point, in other words, even a search initiated at the border could become so attenuated from the rationale for the border search exception that it no longer would fall under that exception. See Molina-Isidoro, 884 F.3d at 295–97 (Costa, J., concurring) (questioning whether search for evidence as opposed to contraband is consistent with justifications for border search exception).

But this is not that case. On the facts here, the link between the search of Kolsuz's phone and the interest that justifies border searches was sufficient to trigger the border exception on any account of a "nexus" requirement. Government agents forensically searched Kolsuz's phone because they had reason to believe – and good reason to believe, in the form of two suitcases filled with firearms parts – that Kolsuz was attempting to export firearms illegally and without a license. See Kolsuz, 185 F. Supp. 3d at 859–60. That is a transnational offense that goes to the heart of the border search exception, which rests in part on "the sovereign interest of protecting and monitoring exports from the country." See Oriakhi, 57 F.3d at 1297; see also Boumelhem, 339 F.3d at 423 (holding that exit search for firearms implicates "significant government interests" not only in controlling exports but also in national security).

This is not a case, in other words, in which the government invokes the border exception on behalf of its generalized interest in law enforcement and combatting crime. Cf. United States v. Vergara, 884 F.3d 1309, 1317 (11th Cir. 2018) (Pryor, J., dissenting) (relying on "general law enforcement justification" to approve evidentiary border searches would "untether the [border search exception] from its justifications"). Here, there is a direct link between the predicate for the search and the rationale for the border exception.

Moreover, as the district court explained, the agents who searched Kolsuz's phone reasonably believed that their search would reveal not only evidence of the export violation they already had detected, but also "information related to other ongoing attempts to export illegally various firearms parts." Kolsuz, 185 F. Supp. 3d at 860. The government emphasizes that finding – not contested by Kolsuz – in its argument before us, and properly so. The justification behind the border search exception is broad enough to accommodate not only the direct interception of contraband as it crosses the border, but also the prevention and disruption of ongoing efforts to export contraband illegally, through searches initiated at the border. See, e.g., Ramos, 190 F. Supp. 3d at 999 (approving post-arrest "investigatory" border search of cell phone for information about larger smuggling organization and "more contraband entering into the country at that time"); United States v. Mendez, 240 F. Supp. 3d 1005, 1007–10 (D. Ariz. 2017) (approving post-arrest border search of cell phone for evidence of additional contraband entering country); cf. United States v. Kim, 103 F. Supp. 3d 32, 44, 46, 59 (D.D.C. 2015) (holding unreasonable forensic search of laptop at border where search was expected to reveal evidence of past but not ongoing criminal activity).

In the circumstances presented here, we agree with the government's bottom line: Because the forensic search of Kolsuz's phone was conducted at least in part to uncover information about an ongoing transnational crime – in particular, information about additional illegal firearms exports already underway, by freight or in the custody of a coconspirator, see Kolsuz, 185 F. Supp. 3d at 860 – it "fits within the core of the rationale" underlying the border search exception. Brief of United States at 19–20.

Maybe I'm misreading this passage, but it strikes me as doing something quite new and significant. It scrutinizes the border search that occured to see if the government's cause for searching in this particular case satisified "a 'nexus' requirement" of showing sufficient connection between the search and "the rationale for the border search exception," requiring a link between the "predicate for the search and the rationale for the border exception." In other words, the Fourth Circuit appears to be requiring the government to identify the border-search-related interest justifying that particular search in order to rely on the border search exception.

Here the search was allowed because it plausibly advanced "the prevention and disruption of ongoing efforts to export contraband illegally." But if a search was undertaken merely to advance the "generalized interest in law enforcement and combatting crime," the opinion suggests, using the fact of the property crossing the border merely as a coincidence, then the border search exception may not apply. As far as I know, this is the first time this limit has been adopted in a precedential opinion.

I'm not yet sure what to make of this. The usual practice in Fourth Amendment law is to balance the interests at a categorical level instead of case-by-case. That is, the court ordinarily considers the interests in the wide category of cases, and then it hands down a clear rule for all cases. That's what Riley did, for example. Riley rejected the idea of having a case-by-case consideration of whether cell phone serches would be reasonable in favor of a bright-line rule: A warrant is required in all cases. You can imagine many different ways of limiting the border search exception (whether for all property or only digital storage devices) that would be similar. Maybe the exception should apply only when entering the country and not exiting; maybe it should allow only a search for contraband and not evidence; etc.

But Kolsuz seems to instead require a case-by-case consideration of whether there is enough of a government interest specifically rooted in the border search exception's animating rationales just to trigger the border search exception, which then (when it applies) also imposes some additional cause requirement. In effect, Kolsuz seems to require both case-by-case justification and then also categorical-rule justification. There must be both enough reason to think that the government's border-search interests are implicated in that case to trigger the border search doctrine, and then enough cause (whatever cause is required) to believe the relevant evidence or contraband will be on the device.

I'm somewhat skeptical that's the best approach. And I wonder, do you read Kolsuz as applying to every border search of every kind, computer or not, just to see if you can trigger the border search exception? If so, how do you measure the government's interest in the routine case where there is no supicion at all? Is there an objective determination of the purpose of the search, as you might have with a special need search like a roadblock? Does it include subjective beliefs, like why an officer happened to make that kind of search, which normally would be forbidden but seemed to be relevant to the court here? This sounds much harder than it may at first look.

Anyway, I suppose Kolsuz may ultimately be another data point on the road to ultimate Supreme Court resolution of how the border search exception applies to computers and cell phone searches. There are a lot of these cases, they're working their way up, and there's a lot of uncertainty about where and how the law should go. As always, stay tuned.