A geofence warrant does not start with a suspect. It starts with a place and a span of time, and it asks a provider to hand over every device that was inside that box. For a decade, courts disagreed about whether that was even a search. In Chatrie v. United States, decided June 29, 2026, the Supreme Court answered: it is. What the Court did not do is tell you how to write one that survives. That part is still yours.
What Chatrie decided
In Chatrie v. United States, No. 25-112 (U.S. June 29, 2026), the Court held 6 to 3, in an opinion by Justice Kagan, that obtaining a person's stored cell-phone location history through a geofence warrant is a search under the Fourth Amendment. A person has a reasonable expectation of privacy in the records of a phone's location, the Court reasoned, even when the government seeks only a limited period and obtains the data from a third-party provider.
That holding resolves a question that had split the lower courts. The en banc Fourth Circuit had declined to suppress the geofence evidence, leaning on the good-faith exception and dividing sharply on whether a search had occurred at all. The Supreme Court took the case to settle the threshold Fourth Amendment question, and it did.
What Chatrie did not decide
The Court stopped there. It did not decide whether the warrant in Chatrie established probable cause or satisfied particularity. It left the reasonableness of the geofence warrant to the lower courts on remand.
That is the part affiants need to sit with. Chatrie tells you a warrant is required. It does not bless any particular geofence warrant, and it supplies no template. The reasonableness question, the one that actually decides suppression, now turns on the two variables you control on the face of the affidavit: the geographic radius and the time window.
The line from Carpenter
Chatrie is the next step on a path the Court started in Carpenter v. United States, 585 U.S. 296 (2018). Carpenter held that acquiring historical cell-site location information is a search that ordinarily requires a warrant, and that the third-party doctrine does not reach long-term location records simply because a provider holds them. Chatrie carries that logic from the cell tower to the geofence: location data is private, and handing it to a company does not make it fair game.
The through-line matters for how you argue these affidavits. The same reasoning that protects cell-site records protects geofence returns, reverse-keyword results, and, increasingly, long-term video surveillance. The en banc First Circuit split evenly on eight months of warrantless pole-camera surveillance in United States v. Moore-Bush, 36 F.4th 320 (1st Cir. 2022), leaving that question open. The direction is consistent: the longer and more comprehensive the surveillance, the weaker the "it was in public" argument becomes.
The good-faith shield is shrinking
For several years, the government won these cases without winning the constitutional argument. Courts suppressed nothing because the law was unsettled and officers had relied in good faith on warrants a magistrate signed.
That cover is closing. The Fifth Circuit has already held, in United States v. Smith, 110 F.4th 817 (5th Cir. 2024), that the geofence technique is a categorically unconstitutional general warrant, because it searches a provider's entire location database without particularized probable cause. The Colorado Supreme Court, in People v. Seymour, 536 P.3d 1260 (Colo. 2023), held that people have a protected privacy interest in their search history, so a reverse-keyword warrant needs individualized probable cause. In both cases the evidence still came in on good faith, and in both the court said the technique was defective. Good faith rewards reliance on unsettled law. After Chatrie, the law is less unsettled every month, and the shield shrinks with it.
Writing a geofence warrant that survives
Treat the request as a search from the first keystroke. Everything that follows assumes a warrant, probable cause, and particularity, written so a reviewing court can test them without guessing.
- Establish probable cause for the place and the window, not just the crime. The facts have to support searching this location across this span of time, and they have to appear on the face of the affidavit.
- Draw the radius to the facts. A geofence that captures a single storefront reads differently from one that captures a mall and three apartment buildings. Describe the geographic boundary and explain why it is no broader than probable cause supports.
- Draw the time window the same way. Minutes, not hours, unless the facts justify hours. State the reason on the record.
- Build in staged, minimized disclosure. Describe a process: an initial anonymized list, a narrowing step tied to the investigation, and only then identifying information for the devices that remain. Courts read a minimization protocol as evidence that the search was tailored, not exploratory.
- Preserve the reasoning. Do not leave the scope decisions in your head. A reviewing court, and a suppression court after it, will test whether the radius and the window were reasonable. The affidavit is where you show your work.
Reverse-keyword and reverse-search warrants carry the same defect and demand the same discipline. They begin with the whole population and work backward, which is the particularity problem stated plainly. If you use one, narrow the query as tightly as the facts allow, document why the population it returns is small and tied to the crime, and develop corroborating leads that do not rest on the reverse search alone.
The standard going forward
Chatrie did not end geofence and location warrants. It ended the argument that they are not searches, and it moved the fight to reasonableness, where it belongs. For the affiant, the takeaway is narrow and practical: the warrant you could get signed in 2022 on a broad radius and a generous window is the warrant that gets suppressed in 2027. The one that survives is particular on its face, minimized by design, and reasoned on the record.
That is drafting discipline, and it is learnable. It is also the discipline the Precision Search Warrants course was built to teach, and the standard the Affiant's Standard manuals apply state by state. Every case named here, and the newer ones as they come down, is tracked and broken down in the free Suppression Database.
Primary sources
- Chatrie v. United States, No. 25-112 (U.S. June 29, 2026). Slip opinion.
- Carpenter v. United States, 585 U.S. 296 (2018).
- United States v. Smith, 110 F.4th 817 (5th Cir. 2024).
- People v. Seymour, 536 P.3d 1260 (Colo. 2023).
- United States v. Moore-Bush, 36 F.4th 320 (1st Cir. 2022) (en banc).
- ASC Suppression Database, Geofence & Keyword Warrants category.
This article is a training and doctrine resource, not legal advice. Governing law varies by jurisdiction and continues to develop. Verify the current rule in your circuit and state, and consult your prosecutor's office before relying on any technique described here.