Before a search warrant will issue, Fourth Amendment jurisprudence requires that it be supported by a probable cause affidavit—a sworn written statement that 1) identifies a specific offense that has been or is being committed; 2) identifies the particular place or person to be searched with specific details allowing the law enforcement officers to locate it or the person; 3) identifies in non-generic terms the contraband, fruits, or instrumentalities of the offense to be seized; and 4) identifies a nexus between the offense, place, and items with sufficient factual circumstances that allows a magistrate to reasonably infer that the items to be seized are present at the describe location to be searched.
A GEOFENCE WARRANT
A geofence warrant—sometimes referred to as a “reverse location” warrant—allows law enforcement officers to demand location data from all devices within a specific geographic location during a specified time period. Instead of targeting a specific person or device, a geofence warrant targets a time and place that allows investigators to work backwards to determine who was there. Geofence warrants generally target location history data, not real-time cell tower pings for a specific device.
Companies that retain location data—like Google with its History/Sensorvault database—are required, under a geofence warrant, to disclose information about all devices within specified coordinates and times.
This search process raises serious Fourth Amendment concerns because it ensnares data on large numbers of individuals not suspected of any wrongdoing. This concern began in 2020 when law enforcement served more than 500 warrants on Google demanding that it search “detailed location information logged by hundreds of millions of devices” and return lists of individuals found in a particular location at specific times.
COURTS SPLIT ON GEOFENCE WARRANTS
In the wake of these kinds of “reverse location” warrants, two federal circuit courts of appeals reached strikingly opposite conclusions about Fourth Amendment challenges to such warrants. Both appeals courts addressed constitutional challenges to geofence warrants in robbery cases in which law enforcement obtained evidence by de-anonymizing location information from private companies like Google.
In December 2023, the Fourth Circuit Court of Appeals in United States v. Chatrie found that two hours of precise data location was only a “brief glimpse” into someone else’s whereabouts that likely did not “offer insights into his habits, routines, and associations.” The Fifth Circuit Court of Appeals, on the other hand, in the following year (August 2024), in United States v. Smith, adopted a more restrictive view of the geofence warrant evidence-gathering process. The Fifth Circuit said that “the potential intrusiveness of even a snapshot of precise location data” involved in geofence warrants should not be understated.” Beyond these constitutional parameters, the appeals also noted that the social impact geofence warrants have on society is equally significant. “Perhaps the most alarming aspect of geofences,” the court said, “is the potential for ‘permeating police surveillance'”— “near perfect surveillance” at that.
Following the lead of these two federal court decisions, the Texas Court of Criminal Appeals (CCA) addressed the geofence warrant issue in Wells v. State in April 2025. The geofence warrant in the Wells case directed Google LLC to turn over to the police “‘ GPS, WiFi or Bluetooth sourced location history data’ corresponding to ‘Initial Search Parameters’ generated from devices that Google’s electronic records showed to have been within certain, particularly circumscribed time and location specifications.”
Wells’ constitutional challenge to the geofence warrant was premised on two arguments: 1) the generalized nature of the warrant “failed to identify a particular suspect and would thus only serve to invade the privacy of any number of individuals who had nothing to do with the capital murder in this case;” and 2) the warrant “lacked probable cause to believe any of the assailants were carrying a cell phone with a Google account.”
At the outset of the CCA’s legal analysis, the court said the geofence warrant affidavit contained ample information that 1) a crime had been committed; and 2) the identity of one or more of the perpetrators of the crime could be identified through a search of Google data. “In this case, the geofence warrant affidavit supplied ample probable cause to believe both that an offense had occurred and that evidence of the identity of one or more of the perpetrators could be discovered by searching the Google database. Moreover, the warrant itself was framed narrowly enough that almost any device found to have been present within its parameters would have belonged to one of the perpetrators, or potentially to a witness who might identify the perpetrators or testify about the offense, but not merely an innocent bystander.”
The Court concluded:
“Assuming that the Fourth Amendment generally requires police to obtain a search warrant for corporate-held location history data, we conclude that the geofence warrant in this case was supported by probable cause and that it satisfied the particularity requirement of the Fourth Amendment.” The Court thus upheld the use of narrowly tailored geofence warrants that were limited in place and time tied closely to the offense.
CONCLUSION
The courts, at both the state and federal levels, will continue to sort through the constitutional weeds that geofence warrants produce. The Wells limited its holding by stating that its legal analysis and conclusions applied “in this case” only, suggesting that, under different circumstances, a geofence warrant could be challenged on constitutional grounds.
The U.S. Supreme Court has agreed to hear Chatrie v. United States, a geofence-warrant case. There are hopes that the Court will create a national rule to guide conflicting lower court approaches.
Geofence warrants, like any other Fourth Amendment secured warrant, are not insulated from constitutional challenge. Defense lawyers must educated themselves on the current law and investigative techniques to properly identify, object and preserve for appeal these very important issues.
