State v. Contreras-Sanchez
The Minnesota Supreme Court held that accessing Google location data through a geofence warrant was a search and that the warrant failed particularity because it left later-stage expansion decisions to police discretion.
Executive Summary
Contreras-Sanchez provides a detailed state high-court framework for evaluating geofence warrants. It rejects both extremes: police do not have unrestricted access to Google location data, but geofence warrants are not automatically unconstitutional in every case.
Investigators used a geofence warrant to identify devices located near a murder scene. The Minnesota Supreme Court held that cellphone users have a reasonable expectation of privacy in location data stored by Google under Article I, Section 10 of the Minnesota Constitution. Government access therefore constituted a search requiring a valid warrant.
The court concluded that geofence warrants are not categorically prohibited general warrants and that the application established probable cause to believe Google’s servers contained evidence of the crime. The particular warrant nevertheless failed because its later stages permitted police to decide which anonymous device identifiers would receive expanded location review without adequate judicial control. The case was remanded for consideration of good faith and harmless error.
Facts and Investigation
Investigators sought evidence concerning the movement and death of a murder victim. They obtained a warrant directing Google to identify devices reflected in its location-history data within a defined geographic area and time period.
The process operated in stages. Google initially supplied anonymized device identifiers associated with the geofence. Investigators could then seek expanded location information for selected identifiers and ultimately request subscriber information associated with devices they considered relevant.
The resulting data helped connect Ivan Contreras-Sanchez to the crime. He moved to suppress, arguing that geofence warrants are unconstitutional general warrants and that this warrant lacked probable cause, particularity, and appropriate limits.
Questions Presented
- Does government access to Google location data constitute a search?
- Are geofence warrants categorically prohibited general warrants?
- Was there probable cause to believe Google possessed evidence of the crime?
- Did the warrant particularly describe the place to be searched and the information to be seized?
Four Holdings
| Issue | Holding |
|---|---|
| Protected privacy | Cellphone users have a reasonable expectation of privacy in location data stored by Google under the Minnesota Constitution. |
| Categorical validity | Geofence warrants are not automatically unconstitutional general warrants; validity depends on the particular warrant. |
| Probable cause | The application established a fair probability that Google’s servers contained evidence of the crime. |
| Particularity | The warrant was insufficiently particular because police retained unchecked discretion to select devices for expanded searches. |
Location Data Was Constitutionally Protected
The court interpreted the Minnesota Constitution independently from the Fourth Amendment and concluded that users possess a reasonable expectation of privacy in location data held by Google. Accessing that information was therefore a search.
The court rejected the proposition that storing location information with a technology provider gives government unrestricted access. It emphasized Minnesota precedent providing greater protection against suspicionless law-enforcement conduct.
The decision rests on an independent state constitutional ground. Agencies cannot assume that federal third-party-doctrine analysis supplies the complete rule in jurisdictions whose constitutions provide greater privacy protection.
Geofence Warrants Are Not Categorically General Warrants
The court refused to declare all geofence warrants invalid. It reasoned that a sufficiently narrow warrant could capture only the suspected offender—for example, where video shows an unknown burglar using a phone during a tightly limited period at an isolated location.
A warrant may therefore avoid the general-warrant problem when geography, time, facts, and staged judicial controls make it particularized to evidence of the offense. Courts must evaluate the actual design and execution of the warrant rather than rely solely on the “geofence” label.
Probable Cause
The court found a fair probability that Google’s servers would contain evidence bearing on the offense. It rejected a categorical requirement that the application establish probable cause as to every unknown person whose data might initially fall within the geofence.
That conclusion did not excuse the government from connecting the requested data to the particular crime. The application still had to establish why location information for the defined place and time would probably contain evidence.
Why the Warrant Failed Particularity
The decisive flaw was discretion. After Google produced anonymized identifiers, the warrant allowed investigators to choose which devices would be subjected to additional location-data disclosure. The issuing judge had not adequately determined those later search boundaries in advance.
A warrant cannot leave the essential decision about whose data receives expanded examination to the uncontrolled judgment of executing officers. The warrant itself—or additional judicial process—must define and supervise the transition from an initial anonymized return to deeper location history and identity information.
The court suggested that independent judicial authorization at successive stages could address this concern by limiting officer discretion before additional data is disclosed.
What the Decision Does—and Does Not—Establish
- The court did not hold that all geofence warrants are unconstitutional.
- It upheld probable cause on the facts presented while invalidating the warrant for lack of particularity.
- The principal constitutional holding rests on the Minnesota Constitution, not a nationwide interpretation of the Fourth Amendment.
- The court did not order final suppression; it remanded for consideration of the good-faith exception and harmless error.
- A narrowly drawn geofence may be valid when facts, geography, duration, and judicial control sufficiently focus the search.
- The opinion does not authorize investigators to broaden an anonymized return without constraints established by a judge.
Agency Guidance
Primary Sources and Further Reading
This monograph is provided for training and general informational purposes. It is not legal advice and does not replace review of the complete opinion, current statutes, controlling federal and state authority, agency policy, provider requirements, technical documentation, or consultation with prosecutors and agency counsel.
© 2026 Shield Public Safety Training. All rights reserved. Reviewed September 3, 2026.