Supreme Court Rules Geofence Warrants Are a Fourth Amendment Search
As we have previously covered, the Supreme Court signaled that they would review the legality of “Geofencing,” the investigation tool police use when they know a crime occurred at a particular place and time, but do not have a suspect, and conduct a search using location data for every cell phone inside a specific area at the time of the alleged crime, when they took up the case and heard oral arguments. The basic idea is to work backward from the location data to acquire a list of possible suspects, which the government argued does not rise to the level of an unreasonable inquiry concerning the privacy protections for individuals guaranteed under the Fourth Amendment. Earlier this week, the Supreme Court issued it opinion on the case, Chatrie v. United States, holding that police conduct a Fourth Amendment search when they obtain a person’s Google “Location History” through a geofence warrant, extending the logic of their previous decision, Carpenter v. United States, which will have real consequences for how location data is used in criminal investigations. To briefly summarize the facts of the case in Chatrie, police were investigating a 2019 bank robbery in Virginia and obtained a geofence warrant for Google’s Location History service, which records a user’s location roughly every two minutes, can place a phone within about twenty meters, and can even estimate which floor of a building the phone is on. Google ultimately produced identifying information for its users in the area at the time of the robbery, including Okello Chatrie, whose data showed he entered the geofenced area shortly before the robbery occurred. Chatrie challenged the investigatory process, and this opinion followed his appeals.
Court Rules Fourth Amendment Protections at Play but Leaves Open Question for Future Challenges
In its ruling, by a 6-3 decision, the Court held that accessing Location History data is a search because a person has a reasonable expectation of privacy in his cell-phone location information. Justice Kagan, writing for the majority, explained that everything the Court relied on in Carpenter to find a search of cell-site data applied “as well or better” to Location History, which is, “’the most sweeping, granular, and comprehensive tool’ existing today for collecting and storing location data.” In arriving at this conclusion, the Court rejected the government’s arguments to the contrary, instead ruling that “an individual has a reasonable expectation of privacy in his cell-phone location information.” First, it refused to recognize a so-called “grace period” for short windows of data that the government argued for, clearly stating that it does not matter that the police obtained only two hours of location information because the Fourth Amendment does not kick in only once an intrusion “goes too far.” Second, the Court declined to apply the third-party doctrine, which generally holds that when an individual shares information with a third party they forfeit their expectation of constitutionally protected privacy, for such intrusive and pervasive information as this type of cell phone data. Essentially that Location History is “not truly shared” in any ordinary sense, and the government argument to the contrary “misapprehends the very nature of modern cell-phone use,” since it is generated automatically when a person uses the ordinary features of a smartphone, and thus a user isn’t opening themselves up to sharing private information with the government, “just by doing the ordinary things cell-phone users do.”
However, the ruling was not an outright win for privacy advocates and those who wish to use it as a definitive ruling for future challenges in similar criminal cases, as the Court decided only that a search occurred. It did not decide whether the search was unreasonable, and it did not decide whether the evidence in Chatrie’s own case will be suppressed, instead opting to remand the issue back to the lower courts. Most strikingly, as the dissent by Justice Alito points out, the Court expressly declined to address the good-faith exception to the exclusionary rule that the Fourth Circuit had previously found would likely allow the admission of evidence in this particular case since the legality of geofence warrants at the time was an open question. The trial court had admitted the evidence under that exception, and the Supreme Court left that question open for the lower court to revisit on remand given this ruling. In other words, the decision does not outright eliminate the good-faith exception in this or similar cases to date, and it does not automatically suppress evidence already gathered through geofence warrants.
In the end, Chatrie confirms that location data held by technology companies is protected by the Fourth Amendment, and its reasoning reaches beyond geofences to other types of investigatory tools using cell phone data. The Court’s rejection of the “short duration” and “voluntary sharing” arguments applies to a wide range of app-generated, cloud-stored personal data that can be accessed via a cell phone, not just Location History. However, while it may not help the defendant who brought the challenge in this Supreme Court case, the case effectively places law enforcement on notice of the issues with Geofencing and an officer seeking to invoke good faith on a defective warrant in the future will fail. For anyone whose case involves location data, a cell phone, or digital records held by a third party, these developments underscore how much can turn on the specific nuanced facts related to the gathering of evidence by law enforcement.
