United States v. Patrick
A divided appellate ruling on a concealed Stingray deployment, a valid arrest warrant, public-place arrest, attenuation, and technological candor.
Executive Summary
Damian Patrick violated parole, prompting a valid arrest warrant. Milwaukee police also obtained a warrant authorizing use of cellphone data to locate him, but the application implied that officers would obtain information from the carrier. Police instead used a cell-site simulator and did not disclose that fact to the issuing judge, district court, defense counsel, or initially the Seventh Circuit. The device led officers to Patrick in a car on a public street, where they arrested him and recovered a firearm. The appellate majority affirmed denial of suppression without deciding whether simulator use was a Fourth Amendment search. Because Patrick’s public arrest rested on probable cause and a valid arrest warrant issued before the disputed tracking, the court held the gun admissible even if the tracking method were removed from the causal chain. Chief Judge Diane Wood dissented, arguing that the concealed technology, incomplete record, non-target collection, and possible warrant mismatch required remand and factual development.
Key Holdings at a Glance
Facts and Procedural History
Patrick was on parole after release from state prison. When he failed to comply with release conditions, authorities obtained an arrest warrant. Police sought a second warrant to use cellphone data to locate him.
A cell-site simulator helped officers pinpoint Patrick. They arrested him while he sat in a vehicle on a public street and found a firearm. Because his criminal record prohibited possession, he was prosecuted under 18 U.S.C. § 922(g)(1), pleaded guilty conditionally, and appealed the denial of suppression.
The Two-Warrant Structure
| Authority | Purpose | Significance |
|---|---|---|
| Arrest warrant | Authorized Patrick’s arrest for parole violations | Predated tracking and supported the public arrest |
| Location warrant | Authorized police to obtain cellphone data to locate Patrick | Application appeared to contemplate carrier-provided data, not a simulator |
| Simulator deployment | Actively induced nearby phones to respond | Raised unresolved search, particularity, and manner-of-execution questions |
What the Court Understood About the Simulator
The majority relied largely on the Department of Justice’s policy description. A simulator presents itself as a cellular access point, causes nearby devices to connect, receives identifying signals, and uses relative signal strength and direction to locate a known device. It does not need to obtain communications content to create constitutional concerns.
The majority recognized a defining difference from carrier process: rather than receiving information about one subscriber from a company, the simulator initially induces multiple nearby phones to communicate with government equipment. Whether and when non-target results are discarded affects minimization, but it does not eliminate the initial collection.
The Fourth Amendment Question the Court Did Not Decide
The government conceded for purposes of the appeal that simulator use was a search. The majority therefore declined to decide whether the technique falls within Smith v. Maryland and United States v. Knotts, resembles a GPS tracker, or becomes more intrusive with greater precision and duration.
Public-Place Arrest
Under United States v. Watson, probable cause generally permits a warrantless arrest in a public place. Here, officers had more: probable cause, knowledge that Patrick was wanted, and a valid arrest warrant. They did not enter a third party’s home or another protected area to seize him.
The majority emphasized that Patrick was visible to the public when arrested. That fact separated the seizure of his person and gun from cases requiring authority to enter a home.
Why the Majority Rejected Suppression
Relying on Utah v. Strieff, the court reasoned that a valid arrest warrant can break the connection between earlier police misconduct and evidence found during an arrest. Patrick’s warrant was not discovered after the fact; officers already knew about it before tracking him.
The majority concluded that the firearm could not become less admissible merely because officers used a disputed method to learn where a wanted person was located in public. Thus, it affirmed without deciding the simulator issue.
Disclosure and Candor Problems
The record revealed the simulator only after Patrick filed his opening appellate brief and an amicus submission prompted the government to acknowledge it. The location-warrant papers appeared to describe obtaining information from the carrier rather than directly operating a simulated tower.
That history undermined informed judicial authorization and made it difficult to determine equipment capabilities, precision, duration, treatment of third-party phones, and whether execution stayed within the warrant’s scope.
Chief Judge Wood’s Dissent
Chief Judge Wood objected that the government appeared to have concealed the Stingray from the issuing judge, the trial court, defense counsel, and the appellate court. She regarded the undeveloped record as inadequate for resolving whether the warrant authorized the device or whether its execution complied with the Fourth Amendment.
The dissent would have remanded for evidence about the simulator’s operation, what it collected, how precisely it located Patrick, and whether it affected third-party phones. Her broader institutional point remains central to agency practice: secret technology cannot receive meaningful constitutional review without accurate disclosure.
Reading Patrick After Carpenter
Patrick predates the Supreme Court’s 2018 decision in Carpenter v. United States, which limited automatic application of third-party doctrine to deeply revealing historical cellular location records. Patrick also involved a known phone, short-term locating, a public arrest, and a preexisting arrest warrant.
Later decisions generally analyze simulators with greater attention to warrants, particularity, homes, minimization, and non-target collection. Patrick remains important for its remedial holding and disclosure controversy, but it is not a complete statement of present simulator law.
Agency Operations Checklist
- Obtain a search warrant that expressly identifies cell-site simulator use unless a recognized exception applies.
- Describe how the device induces target and non-target phones to respond.
- Identify the target device, offense nexus, locations, duration, and activation limits.
- Disclose whether provider data will also be used and distinguish each method.
- Restrict collection and use to signaling data authorized by the court.
- Minimize, segregate, and promptly delete non-target identifiers.
- Stop operation when the target is located or authorization expires.
- Preserve applications, affidavits, returns, logs, settings, deletion records, and all material disclosures.
Litigation and Review Checklist
- Compare the affidavit’s description with the actual equipment and method used.
- Determine when prosecutors, defense counsel, and each court learned of simulator use.
- Obtain technical logs, operating settings, coverage estimates, and non-target handling records.
- Identify all warrants and the timing of issuance.
- Determine whether officers entered a home or made a public arrest.
- Separate the alleged search violation from arrest authority and evidence-seizure authority.
- Analyze standing, causation, attenuation, good faith, and inevitable discovery independently.
- Apply post-Carpenter and controlling state law rather than treating Patrick as resolving the search question.
Frequently Asked Questions
Did Patrick decide that Stingray use is constitutional?
No. The court expressly avoided deciding whether simulator use is a Fourth Amendment search.
Why was the firearm admitted?
Patrick was lawfully arrested in public under a valid arrest warrant that existed before the tracking effort. The majority held that the gun was not suppressible even if the locating method were removed from the analysis.
Did the location warrant name the simulator?
The opinion indicates that the papers implied carrier-provided cellphone data and did not candidly disclose the simulator.
Why is the dissent important?
It documents the disclosure failure and explains why technical facts and non-target collection must be developed before meaningful review.
What is the safest operational takeaway?
Use a detailed probable-cause warrant that expressly describes the simulator and preserve a complete record of deployment and minimization.
Primary Authorities and Related Law
Published appellate opinion and Chief Judge Wood’s dissent.
Read the official opinion
Supreme Court decision addressing attenuation after discovery of a valid arrest warrant.
Read Utah v. Strieff
Supreme Court authority concerning public-place arrests based on probable cause.
Read United States v. Watson
Federal warrant, disclosure, content, deletion, and oversight requirements.
Read DOJ policy
Final Assessment
United States v. Patrick is best understood as a suppression and transparency case, not a definitive holding on whether Stingray use is a search. Its majority shows how a valid preexisting arrest warrant and public arrest can defeat suppression; its dissent shows why incomplete disclosure prevents meaningful judicial control of novel surveillance.