En Banc Fourth Circuit Geofence Decision is Splintered

[EDRM Editor’s Note: The opinions and positions are those of Michael Berman.]

In U.S. v. Chatrie, __ F. 4^th __, 2025 WL 1242063 (4^th Cir. Apr. 30, 2025)(en banc), the Court issued a per curiam affirmance of the District Court’s geofence decision. Fourteen judges joined in that decision. There were eight concurring opinions and one dissent.

[1] Chief Judge Diaz wrote a concurring opinion. [2] Judge Wilkinson wrote a concurring opinion, in which Judge Niemeyer, Judge King, Judge Agee, and Judge Richardson joined. [3] Judge Niemeyer wrote a concurring opinion. [4] Judge King wrote a concurring opinion. [5] Judge Wynn wrote a concurring opinion, in which Judge Thacker, Judge Harris, Judge Benjamin, and Judge Berner joined in full, and in which Judge Gregory joined except as to footnote 1. [6] Judge Richardson wrote a concurring opinion, in which Judge Wilkinson, Judge Niemeyer, Judge King, Judge Agee, Judge Quattlebaum, and Judge Rushing joined. [7] Judge Heytens wrote a concurring opinion, in which Judge Harris and Judge Berner joined. [8] Judge Berner wrote a concurring opinion, in which Judge Gregory, Judge Wynn, Judge Thacker, and Judge Benjamin joined in full, and in which Judge Heytens joined as to Parts I, II(A), and II(B).

[9] Judge Gregory wrote a dissenting opinion.

Michael Berman, E-Discovery LLC.

The entire per curiam opinion is: “The judgment of the district court is AFFIRMED.”

One thing is clear. The law governing geofence warrants is not clear. The issues are important and stand at the intersection of fundamental freedoms, such as the right to be free of unreasonable searches, and the need for effective law enforcement and public safety. Geofence warrants have undeniable value in solving crimes that may otherwise be unsolvable. They also sweep up personal data of innocent people with no connection to those crimes.

In a concurrence in Chatrie, the Chief Judge wrote: “My colleagues have widely divergent views on the intersection of the Fourth Amendment and the groundbreaking investigative tool at issue here. I respect the care and attention they’ve devoted to this matter. But judicial modesty sometimes counsels that we not make grand constitutional pronouncements merely because we can…. This is such a case.”

Geofence and similar warrants have generated a lot of attention. For example, compare Texas Upholds Narrow Geofence Warrant After Melee Resulted in Murder (Apr. 9, 2025), and Geofence Search Warrant Held Valid (Jun. 28, 2024), with Requests for “Tower-Dump” or “Tower-Extraction” Search Warrants Declined Under Geofence Precedent (Mar. 7, 2025).

Prior to the en banc decision, there was a Circuit Split.

The cited court decisions and blogs describe the unique and challenging aspects of these “reverse” warrants, the significant privacy concerns, as well as some of the crimes that they have solved. 

The Chatrie Court carefully explained the three-step process applicable to geofence warrants. Id. at *49, passim. “In conjunction with the Department of Justice, Google developed a three-step anonymization and narrowing protocol in response to these geofence requests.” Chatrie involved an armed robbery at a Virginia credit union. Judge Wilkinson wrote: “Because [the robber] was not apprehended at the scene, he eluded law enforcement for months. Officers were out of traditional leads. Only the geofence warrant eventually allowed police to track Chatrie down and restore a sense of resolution to the community.”

• “In this case, Detective Hylton swore an affidavit for a geofence warrant for Google users’ location history.”
• “The warrant, at Step One, authorized a search for anonymized data of Google users with shared location history for a limited time frame (one hour) and a small geographic scope (150-meter radius) where the crime occurred…. At Step One, Google provided anonymized data for nineteen devices located within the geofence—which included homes, a hotel, a large church, and a restaurant—thirty minutes before and after the robbery.”
• “At Step Two, it authorized a search expanded in both time (one more hour in total) and geographic scope (completely unbounded) and narrowed to a subset of users…. At Step Two, Detective Hylton ultimately identified nine devices and requested additional location data for those devices expanded for thirty minutes before and thirty minutes after the one-hour window authorized at Step One, and without any geographic limitations…. This production allowed Detective Hylton to track those devices outside of the confines of the geofence for an hour before and after the crime was committed.”
• “And at Step Three, the search included non-anonymized, identifying information for a smaller subset…. At Step Three, Detective Hylton requested, and Google provided identifying information about the accounts associated with three of the devices identified at Step Two.”

In Chatrie:

The police charged Chatrie with two crimes related to a bank robbery based on information obtained from Google through a geofence warrant. Detective Joshua Hylton prepared the warrant, which “drew a geofence with a 150-meter radius—with a diameter of 300 meters, longer than three football fields—in an urban environment.” …That radius included the bank and a nearby church. … The warrant “sought location data for every device present within the geofence” for an hour around the time of the robbery (i.e., thirty minutes before and thirty minutes after).

U.S. v. Chatrie, __ F. 4^th __, 2025 WL 1242063 (4^th Cir. Apr. 30, 2025)(en banc).

In the Chief Judge’s concurrence in Chatrie, the good faith doctrine upheld the warrant. “When Detective Hylton applied for the geofence warrant in this case, no court had ruled on the legality of such warrants generally. So he relied on his experience, having successfully obtained three other geofence warrants after consulting with prosecutors before seeking them.” 

The Chief Judge wrote:

A few points bear repeating. [Detective] Hylton reviewed surveillance footage showing that the robber used a cell phone, so he knew that a geofence could reveal both the robber’s identity and any potential co-conspirators. The detective also limited the warrant geographically and temporally.

Id.

The Chief Judge’s concurrence noted the robust debate over these warrants:

One camp insists that disallowing geofence warrants would contravene our precedent, hamstring law enforcement in investigating crimes, and chill innovation at any private company that handles a large database of users. The other camp is just as adamant that granting blanket approval to these warrants would contravene our precedent and compromise the privacy interests of cell phone users.

The balance, ever so delicate, swings from law enforcement and public safety to liberty and privacy interests depending on the record facts. Yet despite a shallow well of information and legal authority and a litany of unanswered questions as to our decision’s reach, my colleagues choose to write broadly. At least in this case, I would opt for restraint and rest on the good-faith exception to the Fourth Amendment.

Id.

This kicked the can down the road. 

My colleagues have done their level best to cut through the Fourth Amendment fog in this case. In contrast, some may say that I’ve done nothing more today than kick the geofence warrant can down the road. Others may complain that I’ve offered no guidance to law enforcement and magistrates about the reach of the Fourth Amendment in the digital age, or worse still, that I’ve resorted to “judicial abdication,” opinion of WYNN, J., at 35 (concurring).

But what guidance have my colleagues given today? Instead of a Fourth Amendment compass, we’ve gifted law enforcement (and the public) a labyrinth of—by my count, nine—advisory opinions, many pointing in different directions. [Emphasis added].

Id.

The Chief Judge quoted Justice Frankfurter’s comment that, when addressing new problems, we should take care not to “embarrass the future.” The concurrence concludes:

In short, there are times to make sweeping constitutional pronouncements (with attendant consequences) and times to wait. Humility in the face of the unknown—whether it be the legal ramifications or practical consequences of our decision, or Google’s own changing policies—“counsels caution.”

Id.

Judge Wilkinson’s concurrence begins: “With due regard for my fine colleagues, there was no search here. And even if one were to assume there was a search, there are many good reasons why courts should respectfully reject the assault on geofence warrants mounted by appellant….” Two points were: 1) Chatrie volunteered incriminating information to a third party; and, 2) the Fourth Amendment requires a balancing of individual privacy and public safety.

[U]nder appellant’s view, local, state, and federal officers would lose the tools they need to protect the public from the modern-day criminal. More cold cases would go unsolved. Think of a murder where the culprit leaves behind his encrypted phone and nothing else. No fingerprints, no witnesses, no murder weapon. But because the killer allowed Google to track his location, a geofence warrant can crack the case…. Taking this tool of last resort out of law enforcement’s hands would leave these case files collecting dust. The Fourth Amendment does not require allowing criminals to take advantage of cutting-edge technologies while preventing the government from doing the same. Technology enables the lawbreaker. Courts disable the government. This imbalance will only grow with time.

Id.

Addressing the request for a categorical invalidation of geofence warrants, Judge Wilkinson wrote: “Excluding this evidence from trial gives these criminals, in the words of the Supreme Court, ‘a get-out-of-jail-free card.’” His Honor wrote: “The sheer breadth of appellant’s position is disquieting. Those who support it seek a broad judicial declaration that geofence warrants would be unconstitutional in all their forms, no matter how specific and particularized. The geofence warrant here was closely confined to a particular time, place, and incident. There can be abuses to be sure, but courts can review the temporal and spatial character of these warrants as we would any Fourth Amendment claim. To strike the warrant down here comes pretty nearly to invalidating it everywhere. No matter says appellant. All such warrants are on the chopping block.”

In a statement that mirrors the Chief Judge, Judge Wilkinson noted:

As we contemplate the future, Fourth Amendment interpretation leads to twin risks. One is the risk that privacy will succumb to the evermore invasive technological capabilities at the hands of an evermore intrusive state. The other risk, which is just as real, is that of privileging those who break the law over those who would enforce it. Either future portends stark consequences for society where individual dignity cannot in the end be divorced from an intuitive sense of personal safety.

Id.

Noting the violent nature of the charged crime and the need for geofence evidence to solve it, Judge Wilkinson’s concurrence held that it was reasonable in this instance.

Judge Niemeyer’s concurrence applied a “commonsense analogy.” His Honor’s decision analogized a Supreme Court precedent that “left untouched” “law enforcement’s practice of collecting and following ‘markers,’ or clues, voluntarily left behind and abandoned by a person at the scene of a crime or in connection with the crime…. Thus, law enforcement is entitled to retrieve boot prints, tire tracks, shell casings, a scarf or a cap, and items left with fingerprints or DNA on them. Similarly, they can retrieve third-person records of a suspect’s presence, such as pictures and videos taken routinely at the scene, records of tolls paid, or records of credit card transactions.” Judge Niemeyer saw the location data as a marker left behind by Chatrie. The concurring opinion also points to the limits – the warrant was limited to the scene and time of the crime.

Judge Wynn’s concurrence suggested that the substantive Fourth Amendment issue should be decided before a decision on good faith. His Honor wrote: “The constitutional question in this case has been fully briefed, argued and exhaustively debated—not only by the parties but by amici and members of this Court. And it is unclear what future case could better tee up the issue. Judicial modesty does not demand judicial abdication.” 

Judge Wynn wrote that the warrant was a Fourth Amendment search. Relying on Supreme Court precedent, Judge Wynn suggested “a multifactor approach to assessing reasonable expectations of privacy in digital information.” One of many interesting points is that Judge Wynn noted that even a very limited time frame could disclose sensitive and private information of innocent people. 

As to the argument that Chatrie voluntarily disclosed the information to Google: “That argument is several decades beyond its time…. [I]t would be a grave misjudgment to conflate an individual’s limited disclosure to Google with an open invitation to the state.”

Today, the Court declines to decide whether law enforcement may access Location History data without a warrant. In doing so, it leaves unresolved a question of immense constitutional significance: whether the Government may track a person’s movements—potentially for weeks or months—without judicial oversight. That uncertainty threatens not only Chatrie’s privacy, but the privacy of all Americans.

Instead of addressing that compelling constitutional issue, this Court takes refuge in the good-faith exception—and thereby clears the path for widespread, surreptitious police surveillance. The result is plain. It leaves the door open for law enforcement to monitor religious services, political protests, gun shows, union meetings, or AA sessions—all without a warrant, all without judicial oversight or accountability. The technology at issue here does not merely capture a person’s location at a single moment; it allows the Government to “reconstruct a person’s movements.”

Id.

Judge Richardson’s concurrence turned in large part on a description of the technology – specifically location history – and describes the history of geofence warrants, including Google’s required three-step procedure. Id. at *28-29.

Whatever [the user’s] choice, Google will honor it. From start to finish, then, the user controls how much Google tracks and stores his Location History data.

Id.

Instead of relying on the good faith exception, Judge Richardson wrote that “Chatrie did not have a reasonable expectation of privacy in two hours’ worth of Location History data voluntarily exposed to Google. So the government did not conduct a search when it obtained this information from Google, and so no warrant was required at all.” While recognizing that the third-party doctrine was difficult to apply in the digital age, Judge Richardson applied it.

In another concurrence, Judge Heytens wrote that the fact of a Fourth Amendment violation – whether or not it occurred here – does not necessarily lead to exclusion of evidence. The goal of the Constitutional provision is to deter misconduct. Here, the legal landscape was uncertain at the time and “there were no clear guideposts to follow.” And, the officer had obtained three other geofence warrants in the past. Here, according to Judge Heytens, there was no need to deter improper conduct.

Judge Berner’s concurrence again noted the competing concerns:

Our Fourth Amendment jurisprudence recognizes that the balance between individual privacy and public safety is a delicate one. Technology’s threat to that balance lies at the heart of this case. Prohibiting the government from using geofence warrants in all but the rarest of cases would unnecessarily frustrate criminal investigations. At the same time, allowing the government warrantless access to individuals’ non-anonymous location data would swing the pendulum too far in the other direction.

Id.

His Honor wrote:

Unlike our colleagues on the Fifth Circuit, I do not believe that geofence warrants are categorically unconstitutional. See United States v. Smith, 110 F.4th 817, 838 (5th Cir. 2024). Individuals lack a reasonable expectation of privacy in Location History data that is truly anonymous, meaning that—as evaluated at the time of the government’s request—the data is not likely to be traceable to specific individuals. An individual does not have a reasonable expectation of privacy in the mere fact that a certain number of unknown individuals were located near a public place at a particular time, even if he happened to be one of those individuals. I would thus hold that Government’s first request to Google did not result in a Fourth Amendment search. Because of the (1) short duration of the request, (2) limited size of the geofenced area, and (3) public nature of the geofenced area, the Location History data that the Government initially requested from Google was not likely to be traceable to any specific individual, including Chatrie. Consequently, the initial request did not infringe upon Chatrie’s reasonable expectation of privacy.

Id.

Judge Berner wrote that: “I would hold that law enforcement conducts a search when it obtains any amount of an individual’s Location History data that is non-anonymous.” The first step in the Chatrie methodology did not obtain such data. The concurrence explains:

The pseudonymized Location History data obtained through the Government’s first request was anonymous. In that request, the Government sought data depicting all Google users’ movements within a 150-meter radius, which encompassed primarily public streets and stores, over a one-hour timeframe. Absent some stroke of luck for the Government, it was exceedingly unlikely that Google’s response would reveal the identities of the pseudonymized individuals within that geofence perimeter, even if “analyzed with other available information.”

Id.

Anonymity was viewed as an important factor:

The revealing nature of Location History data depends on whether it is anonymous. Though anonymous Location History data is not particularly sensitive, non-anonymous Location History data is highly revealing.

Id.

His Honor wrote:

Let’s take an example. If the government were to look at pseudonymized Location History data generated within a defined section of I-95 between 7:00 am and 9:00 am on a weekday, it is not likely to be able to determine the identities of the individual drivers. If, on the other hand, the search area were unrestricted or included residential neighborhoods, two hours of Location History data during that same time period could reveal that a pseudonymized Google user traveled from a particular home to a particular company’s office building. The government could readily determine that individual user’s identity by, for instance, looking at property records and running a LinkedIn search.

Id.

Judge Berner explained that the second request to Google drilled down to where it was no longer anonymous. Id. at *42. His Honor found a privacy interest in those data. His concurrence relied on evaluating the “type of data” rather than the amount gathered in a limited time frame. The opinion noted that the detective could have gone back for a new warrant for the non-anonymous data, but did not do so.

As to the third-party doctrine: “Whether the disclosure of data to a third party was ‘voluntary’ is not a binary inquiry but a matter of degree. Here, this factor does not tip decisively in favor of either party.”

Judge Berner wrote that the Fifth Circuit held that geofence warrants are categorically unconstitutional. He disagreed with that holding. His Honor concluded:

Though this case involves advanced technology and difficult legal questions, complexity does not absolve us of our obligation to interpret the Constitution. I see little benefit in postponing these issues until another day. Deciding this case without reaching the Fourth Amendment issues merely perpetuates the constitutional fog that will allow unlawful searches of Location History data to continue to evade consequence through the good-faith exception.

In my view, the government conducts a Fourth Amendment search when it obtains non-anonymous Location History data. This includes pseudonymous data that is likely to be traceable to a particular individual. Therefore, I would find that the Government conducted a search of Chatrie through its second and third requests to Google. Because the Government relied on a warrant that was not supported by probable cause, its search of Chatrie violated the Fourth Amendment.

Id.

Judge King concurred in an opinion primarily incorporating others.

Judge Gregory dissented.

To consider these important questions––whether there is a Fourth Amendment violation, and whether the Leon good faith exception should apply––requires courts to examine the underlying warrant and the circumstances pertaining to its issuance and execution. That task will sometimes require courts to wade through murky constitutional and doctrinal waters to provide necessary guidance to district courts, attorneys, law enforcement, and citizens alike. But our Court has decided not to do so here, opting instead to sidestep the complex issues presented in this case. The majority of this Court has decided to affirm the district court’s opinion, but its reasoning is fractured.

I concur largely in the writings of Judge Wynn and Judge Berner in finding that there was a constitutional violation, as I believe that the geofence warrant at issue glaringly infringed on the Fourth Amendment. However, I write separately to explain why I believe the good faith exception is inapplicable in this case. [Emphasis added].

Id.

That explanation begins at page *49 of the opinion.

[I]t is a perilous day when our Fourth Amendment protections lie in the hands of a private company, and constitutional rights should not and cannot be defined by the internal policies of a private corporation. This is so even where the process was created with input from law enforcement. To that point, I note that the government and some of my colleagues highlight that Google’s process was created in conjunction with the Department of Justice. Notably, the government’s interest in defining the Fourth Amendment right is no greater than that of the defense counsel, other attorneys, and the public at large—none of whom were offered a seat at the table. And, even if Google had opened the forum to all potential stakeholders, its process would still lack finality because corporations lack the authority to interpret the Constitution. That responsibility belongs to the courts, and we must not relinquish it to those not charged with protecting the Constitution or otherwise abdicate it because the task seems too difficult. [Emphasis added].

Id. at *49.

 The dissent wrote:

Law enforcement should not be denied the benefit of the efficiencies that emerging technologies offer. However, when seeking digital evidence, officers must demonstrate at least the same level of supporting information necessary to justify the search of physical places and things. In other words, officers should not be permitted, with aid of an unbridled warrant, to shake the proverbial digital tree without an objectively reasonable belief that the warrant and the manner of its execution are consistent with the Fourth Amendment.

Id.

Judge Gregory wrote: “Some cry ‘novelty’ and ‘technological change’ as an excuse for a fundamental departure from our constitutional principles. But one thing is for certain: technology will continue to shift, but the basic protections of the Fourth Amendment must remain. The people’s rights against unreasonable searches and seizures cannot not bend to accommodate the volatility of technology. Rather, new technologies must bend to accomplish the vitality of the protections guaranteed to the people under the Fourth Amendment. Regrettably, the ever-increasing extension of the good faith exception to the exclusionary rule has turned this sacred principle of Fourth Amendment interpretation on its head.”

As if there was not enough complexity, in the Chief Judge’s Note 6, the opinion states that:

To add more uncertainty, Google intends to change its Location History policy so that it will no longer be able to respond to geofence warrants. See Smith, 110 F.4th at 822 n.3.; see also Marlo McGriff, Updates to Location History and New Controls Coming Soon to Maps, Google (Dec. 12, 2023), https://blog.google/products/maps/updates-to-location-history-and-new-controls-coming-soon-to-maps/ [https://perma.cc/7ZMS-RHF9]. [Emphasis added].

Id.

In Note 16, the Chief Judge’s opinion states:

Ironically, decisions like this one could also hinder legitimate law enforcement efforts. Shortly after the first oral argument in this case, Google—apparently predicting the panel majority’s flawed reading of Carpenter—announced its intention to stop centrally storing users’ Location History data, thereby reducing the potential for legitimate investigatory uses of Location History data, even with a warrant. See Cyrus Farivar & Thomas Brewster, Google Just Killed Warrants That Give Police Access to Location Data, Forbes (Dec. 14, 2023), https://www.forbes.com/sites/cyrusfarivar/2023/12/14/google-just-killed-geofence-warrants-police-location-data [https://perma.cc/GCP9-QPBG].

Id.

And in Note 1, Judge Richrdson wrote: “Google has announced changes to its Location History setting. See Marlo McGriff, Updates to Location History and New Controls Coming Soon to Maps, Google (Dec. 12, 2023), [https://perma.cc/Y62G-GBUW].” His Honor noted that the facts presented in Chatrie, may not reflect “Google’s technology and practices now or in the future.”

Assisted by GAI and LLM Technologies per EDRM GAI and LLM Policy.