Texas Stamp


PD-0669-23 01/24/2024

1. “Whether the Court of Appeals correctly determined the legality of geofence warrants, an issue of first impression in Texas and an important question of state and federal law that has not been, but should be, settled by the Court of Criminal Appeals.”

2. “Whether the Court of Appeals correctly determined the reliability of Google data, an issue of first impression in Texas and an important question of state and federal law that has not been, but should be, settled by the Court of Criminal Appeals.”


When investigating a shooting and murder at a residence, police sought a geofence warrant to search location history data from mobile devices in the area at the time of the offenses.  The officer’s affidavit stated that (1) four suspects gathered in a parking lot across the street from the house where the offenses occurred, (2) it’s likely that at least one suspect enabled Google location services, and (3) home-invasion perpetrators are known to keep an open line of communication with a look-out person outside the house.  A judge issued a warrant outlining a process for greater and more specific search parameters: first, anonymous user information; second, anonymous user information derived from a larger area and increased time block based on law enforcement’s narrowing of users from the first search; and third, identified user information.  The investigation ultimately led to Wells being charged with capital murder.  The trial court denied Wells’ motion to suppress, which argued that “the search was an unreasonably broad invasion of privacy and unsupported by probable cause.”

On appeal, the court of appeals held that the warrant was sufficiently narrow as to time and place.   It rejected Wells’ argument that it impermissibly included third parties merely present in the area when the offenses were committed.  It reasoned that it was unlikely to identify persons who weren’t either suspects or witnesses to the offenses.  It also rejected Wells’ argument that the State was required to present specific evidence that the suspects carried cell phones at the time of the crime.   Probable cause is about probabilities, and cell phones are ubiquitous.  Further, police sought the identities of persons at the scene through location data.  Last, the good-faith exception would apply.

Next, the court of appeals addressed Wells’ complaint that the Google location history data was unreliable.   In rejecting this argument, the court observed that it and other courts have already recognized its reliability.  And because a map based on CSLI from Wells’ service provider would have been admissible, the Google data combined with the CSLI is significantly more reliable.   Further, because Google also uses GPS, it’s more precise than CSLI.   As applied here, the State’s expert independently verified the raw data’s accuracy with other evidence.  Therefore, Google’s unreviewed algorithm that combines the raw data was irrelevant. 

On the geofencing issue, Wells contends that the lower court’s decision omits a nexus requirement between the offense and the presence of a cell phone and between the use of Google and any perpetrators or witnesses.  Additionally, even if the court had required a nexus, the rationale that there was a lookout with a cell phone is purely speculative.   Wells also asserts that the three-step search protocol gave police unchecked discretion to obtain more information without judicial oversight.  Finally, good faith would be inapplicable because the warrant affidavit omitted key facts related to the breadth and scope.

Second, on reliability, Wells points out that one federal court ruled against the admissibility of similar data.  Here, “[n]o one could verify how Google obtained the data it turned over, its process for culling and delivering data in response to a warrant or court order, or its proprietary algorithm.”  In its business affidavit, Google did not explain how it retains and turns over data.  Further, there are no peer-reviewed studies or known error rates.

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