Federal Judge Suppresses Evidence From Warrantless ALPR Search

Federal Judge Suppresses Evidence From Warrantless ALPR Search

A federal judge in Tulsa granted a motion to suppress on October 1, 2026, holding that a sheriff's deputy conducted a Fourth Amendment search when he queried a month of historical license plate reader data without a warrant. All evidence from the resulting traffic stop was suppressed.

Information last verified on October 4, 2026. This is a developing story; we update it as the record changes.

Jurisdiction scope: This ruling comes from one federal trial court, the U.S. District Court for the Northern District of Oklahoma. It is persuasive authority at most. It does not change Oklahoma statutory law, it does not bind state courts in Oklahoma, and it does not bind any federal court anywhere, including the judge of the same district who ruled the opposite way.

What Happened

On October 1, 2026, Judge Sara E. Hill issued a 38-page Opinion and Order in United States v. Melisa Susan Kyle, No. 4:26-cr-00189-SEH, in the U.S. District Court for the Northern District of Oklahoma. The order, filed at ECF No. 62, granted the defendant's Opposed Motion to Suppress, ECF No. 47. The CourtListener docket for the case records the motion as filed August 3, 2026, the government's response at ECF No. 50 on August 10, 2026, an evidentiary hearing before Judge Hill on August 27, 2026, and the opinion granting the motion entered October 1, 2026.

According to the opinion's findings, Tulsa County Deputy Sheriff Freddie Alaniz was parked beside a highway watching traffic when his patrol vehicle's exterior cameras read the California plate on a Mazda SUV. The opinion states that Alaniz "pulled his vehicle onto the highway to follow the Mazda for no apparent reason other than the fact that it had a California license plate," and that he simultaneously ran a query on the plate through the Flock system. The court found that Alaniz had access to at least two ALPR systems, Flock and VehicleManager, and that the reasons he entered for the queries were "traffic violation" and "investigation," even though at that moment "all Alaniz knew was that the vehicle had a California license plate."

The opinion describes what that query returned. The court found that Alaniz "had access to an entire month's worth of location data tied to the license plate on Kyle's car, including more than fifty sightings across multiple states," citing the government's own exhibit at ECF No. 50-3. The opinion also notes a gap in the deputy's coverage: he did not have access to Flock data from California.

Alaniz then stopped the Mazda. The court upheld that stop. It found an objectively reasonable basis under 47 O.S. 11-310, the Oklahoma statute providing that a driver "shall not follow another vehicle more closely than is reasonable and prudent," because the record showed roughly 30 feet between the Mazda and the car ahead of it.

Where the government lost was everything after the stop ended. The court found that Alaniz returned the driver's license, issued a written warning, then asked for consent to search, was refused, and immediately announced that the driver was detained for a dog sniff. Applying Rodriguez v. United States, 575 U.S. 348 (2015), as construed by the Tenth Circuit, the court fixed the Rodriguez moment at the return of the license, which it said the detention announcement only made clearer, and walked through each of the six reasons the government offered for reasonable suspicion: the short turnaround trip, the luggage, the cigarette, the rental car, nervousness, and a marijuana disclosure that the court found came only after the detention had already begun. It gave two of them no weight at all, the cigarette and the rental car, and gave the rest only a little. "At the end of the day," the court wrote, "the unavoidable hole in the record for the government is that it does not tie any of this to a specific, articulable reason why any one or combination of factors gave Alaniz a reasonable basis to believe Kyle engaged in criminal activity."

Then the court reached the ALPR question, and this is the part that makes the ruling unusual. It began by conceding how isolated its position is. "Neither the Tenth Circuit nor the Supreme Court have decided whether law enforcement's use of ALPR technology is a search for Fourth Amendment purposes," the opinion says, and "it appears that nearly every court examining the issue to date has determined that ALPR technology use is not a search under the Fourth Amendment because people have no reasonable expectation of privacy in their movements on public streets." It then named three Oklahoma federal decisions that went that way: United States v. Schoggins, No. CR-25-189-JFH, 2026 WL 713083 (E.D. Okla. Jan. 28, 2026); United States v. Brown, No. CR-25-188-D, 2025 WL 2444596 (W.D. Okla. Aug. 25, 2025); and United States v. Acosta, No. 25-CR-00239-GKF, 2025 WL 2427700 (N.D. Okla. Aug. 22, 2025).

The court's disagreement with those cases turns on how much weight United States v. Knotts, 460 U.S. 276 (1983), can still carry. Knotts held that a person traveling on public thoroughfares has no reasonable expectation of privacy in his movements from one place to another, but it also expressly reserved the question of "dragnet type law enforcement practices." Judge Hill took up that reservation directly:

More than 40 years have passed since the Supreme Court's decision in Knotts, and this Court is now faced with technology that appears to be approaching the dragnet type law enforcement practice Mr. Knotts warned of. Therefore, lower courts need to reexamine the result in Knotts as technology advances past the rudimentary beeper in that case.

United States v. Kyle, No. 4:26-cr-00189-SEH, ECF No. 62, at 31 (N.D. Okla. Oct. 1, 2026).

The opinion then built its holding on Carpenter v. United States, 585 U.S. 296 (2018), and on the Supreme Court's 2026 geofence decision, Chatrie v. United States, which it cites as 609 U.S. ___, 146 S. Ct. 2193 (2026). It acknowledged that Carpenter distinguished phones from cars, quoting the passage that "[w]hile individuals regularly leave their vehicles, they compulsively carry cell phones with them all the time." But it drew out the principle both cases share: that people "have a reasonable expectation of privacy in the whole of their physical movements."

The court was explicit that ALPR data is less precise than phone data, and equally explicit about why it thought that did not save the search:

This is a type of indiscriminate mass surveillance. It is not targeted on a single individual, as in Carpenter. It is a tool that collects information about all vehicles that pass by any network-connected camera at all times, and it serves up the information to law enforcement on demand.

Id. at 34.

The holding itself is narrow in wording and wide in implication:

The Court finds that because the ALPR systems Alaniz used to search Kyle's historical location information intruded on her reasonable expectation of privacy in the whole of her physical movements, it was a search under the Fourth Amendment. Based on the information in the record, the only reason Alaniz conducted that search was because he saw her license plate was from California. That search was not supported by probable cause, and it was done without a warrant in violation of Kyle's Fourth Amendment rights.

Id. at 37.

Because the deputy began following the Mazda while running the query, the court found a nexus between the ALPR search and everything that followed, and suppressed all evidence obtained after the search began as fruit of the poisonous tree. On the prolonged-stop ground it separately suppressed all evidence obtained after the license was returned. In both places the court's entire treatment of the exclusionary rule came down to one concluding sentence: the government did not identify any exception. The opinion contains no good-faith analysis.

Two things the opinion does not do are worth naming, because the ruling is easy to overstate. It does not announce a rule for a single plate read. The object of the holding is the query of historical network data, and the court did not separately decide whether the camera on the patrol car capturing one plate, standing alone, is a search. And it does not construe Oklahoma's ALPR statute. The government argued that state ALPR law is irrelevant to the Fourth Amendment analysis; the court resolved the case on federal constitutional grounds and never cited the Oklahoma provision at all.

What the Law Actually Says

The Fourth Amendment protects against unreasonable searches and seizures, and the threshold question in any case like this is whether government conduct counts as a "search" in the first place. Under the framework the Kyle opinion applies, drawn from Katz v. United States, 389 U.S. 347 (1967), it does when the government intrudes on an expectation of privacy that society is prepared to recognize as reasonable.

For location data, the governing case is Carpenter, which held that acquiring historical cell-site location records is a search. Carpenter rests on the idea that people retain a reasonable expectation of privacy in the whole of their physical movements even though individual movements occur in public. In June 2026 the Supreme Court extended that reasoning to geofence requests in Chatrie v. United States, No. 25-112, decided June 29, 2026 and reported at 609 U.S. 605. The Court's own summary of that case states that officers "conducted a Fourth Amendment search when they acquired Chatrie's location data from Google because an individual has a reasonable expectation of privacy in his cell-phone location information." We covered that decision when it came down in our report on the Supreme Court's geofence warrant ruling.

Running against that line is Knotts, the 1983 beeper case, which is the authority most courts have used to hold that ALPR queries are not searches. Nothing in Kyle overrules Knotts. The opinion argues that Knotts should be read against its facts and that its own reservation about dragnet practices has now been triggered. Other judges have read the same precedents and reached the opposite result, which is exactly why the opinion lists them.

Oklahoma statutory law does not fill this gap. The state has one plate reader statute, 47 O.S. 7-606.1, and it is narrow. Read directly in the compiled Title 47 published by the Oklahoma Legislature, it creates the Uninsured Vehicle Enforcement Program, administered by district attorneys and the District Attorneys Council, and authorizes participating agencies to use plate readers "for the investigation, detection, analysis or enforcement of Oklahoma's Compulsory Insurance Law." Subsection (E) sets no fixed retention period: program data is kept while it serves as evidence of an insurance violation and must then be deleted or destroyed. Subsection (F)(1) bars any agency or entity authorized to operate under the program from selling captured plate data or sharing it for any purpose not expressly authorized by the section. Subsection (G) says the program provisions do not apply to, or prohibit, other plate reader systems used by individuals or private entities for purposes not otherwise prohibited by law.

That statute is not a general warrant requirement, and it is not what the Kyle court applied. Our guide to Oklahoma's license plate reader statute walks through the full text. The practical effect is that in Oklahoma, as in most states, the limits on police access to historical plate data are whatever courts say the Fourth Amendment requires, plus whatever an individual agency's own policy and vendor contract impose. Our state-by-state comparison of plate reader rules shows how unevenly the states have legislated here.

It also helps to be precise about the technology the court was describing, because the opinion's reasoning depends on it. The court found that Alaniz's patrol car cameras feed into the same fixed-camera networks he could then query, that the systems hold a continuously updated location history for every vehicle the network sees, and that it is unclear from the record how long the data is kept or who keeps it. If you want the underlying mechanics, see our explainer on how Flock camera networks collect and share data.

The same question is in front of an appellate court already. We have been following the Fourth Circuit litigation over Norfolk's Flock camera network, which presents the Carpenter-versus-Knotts problem on a civil record rather than a suppression motion.

Analysis: Why This Matters

The following is analysis from the Recording Law Editorial Team.

The most useful thing about this opinion is its honesty about its own position. A district judge who writes that "nearly every court examining the issue to date" has gone the other way, and who then lists three decisions from her own state including one from her own district, is not pretending to apply settled law. She is inviting review. That framing matters for how much weight anyone should give this ruling: it is a well-reasoned outlier, written to be appealed or adopted, not a statement of what the law currently is in Oklahoma.

The second thing worth noticing is that the suppression order does not actually depend on the ALPR holding. The court resolved the prolonged-stop question first and suppressed everything obtained after the license was returned on that ground alone, applying ordinary Tenth Circuit reasonable-suspicion doctrine to a set of facts that courts have rejected many times before: an unusual travel itinerary, too many bags, a cigarette, a rental car, and nervousness. The ALPR section is a second, independent ground. If an appellate court disagrees about ALPR, the suppression could still stand. If it disagrees about reasonable suspicion, the ALPR holding is still there. That structure makes the opinion harder to dismantle on appeal, and it also means the headline about plate readers is sitting on top of a fairly conventional traffic-stop ruling.

Third, the factual record here is narrower than the doctrinal question. The court emphasized the scale of what the deputy could reach: a nationwide network, roughly 30 days of history, more than fifty logged sightings, and a query whose stated justification was a "traffic violation" that had not yet occurred when the query was run. A future case with a single plate hit, or a query run with an actual investigative predicate, is not the same case, and the opinion does not pretend to decide it. Courts generally draw the Carpenter line by volume and duration rather than by technology type, and the quantity findings in this opinion are doing real work.

The weakest part of the order, from the government's perspective, may also be the easiest to attack: the exclusionary-rule analysis comes down to one concluding sentence in each place, resting entirely on the observation that the government never argued for an exception. Good faith is the obvious argument in a situation where three published decisions in the same state told officers that ALPR queries were not searches. The opinion does not reject that argument. It records that nobody made it. That is a thin foundation if this reaches the Tenth Circuit, and it is the kind of gap a reviewing court can fill without touching the constitutional holding at all.

Finally, the policy passages in the opinion are going to be quoted far more often than the holding. The court's hypothetical about a stranger announcing "I have been following your car for the last 30 days," and its list of what plate data can expose about fertility clinics, liquor stores, doctors and lawyers, are the kind of writing that shows up in briefs and legislative testimony for years. Whether or not this particular order survives, that framing of plate reader networks as "indiscriminate mass surveillance" is now in a federal opinion, and other litigants will use it.

How This Affects You

If you are wondering what this changes for an ordinary driver in Oklahoma or anywhere else, the honest answer is: not much yet, and nothing automatically.

A single district court suppression order does not stop any agency from running plate reader queries. It does not require Oklahoma police to get a warrant before searching Flock or VehicleManager. It does not create a right to have your plate data deleted, and it does not give you a claim against a police department or a camera vendor. It controls one piece of evidence in one federal criminal case.

What it does provide is an argument. Defense counsel in federal and state criminal cases where historical plate reader data drove the investigation now have a reasoned federal opinion to cite, and the government has three Oklahoma decisions to cite back. If you are a criminal defendant whose case involved an ALPR query, that is a question for your own lawyer and for the record in your specific case, not something that resolves from a news article.

For everyone else, the useful takeaway is informational. Plate reader networks retain where your car has been for some period that is set by vendor contract and agency policy rather than by Oklahoma statute, those records are routinely searchable by officers in other states, and the court in this case could not determine from the record how long the data is kept or who keeps it. If you want to know what your own local agency does, agency ALPR policies and vendor contracts are usually obtainable public records, though Oklahoma's statute does place an Open Records Act exemption on some plate reader data. That is the layer where most of the real rules currently live.

This is general legal information, not legal advice. It describes one Opinion and Order from the U.S. District Court for the Northern District of Oklahoma applying federal Fourth Amendment law, along with Oklahoma statutory provisions in Title 47. It does not describe the law of any other state, and a federal district court ruling binds no other court. Verified October 4, 2026. If a plate reader search affected your case, speak with a licensed attorney in your jurisdiction.

Related articles

• Supreme Court rules geofence warrants are a Fourth Amendment search
• Oklahoma license plate reader laws
• License plate reader laws by state
• What are Flock cameras and who sees the data
• Fourth Circuit weighs Norfolk's Flock camera network

Last updated: 2026-10-04. This is a developing story; details verified as of 2026-10-04.

Frequently Asked Questions

What did the court actually hold in United States v. Kyle?

Three separate things. First, the traffic stop was lawful at its inception because the deputy had an objectively reasonable basis to believe the driver was following too closely under 47 O.S. 11-310. Second, the deputy unlawfully prolonged the stop after returning the license, because he lacked reasonable suspicion of any other crime at that moment, so everything obtained after that point was suppressed. Third, and independently, the warrantless query of historical ALPR data through Flock and VehicleManager was a Fourth Amendment search, and because the government identified no exception to the exclusionary rule, all evidence obtained after the search began was suppressed as fruit of the poisonous tree.

Does this ruling mean police need a warrant to search license plate reader data?

Not as a general matter. The decision is from one federal district judge in the Northern District of Oklahoma and binds no other court. The opinion itself states that neither the Tenth Circuit nor the Supreme Court has decided whether ALPR use is a search, and that nearly every court to address the question so far has held it is not. It names three Oklahoma federal decisions reaching the opposite result.

How much data did the ALPR search return?

The opinion states the deputy had access to an entire month of location data tied to the plate, including more than fifty sightings across multiple states, citing a government exhibit. It also finds he had access to at least 30 days of vehicle location information in many states at the time, but not data from California.

Which plate reader systems were involved?

The opinion names two: Flock and VehicleManager. The court found the deputy's own patrol vehicle carried exterior cameras that read passing plates and fed into those larger fixed-camera networks, and that both systems ask a user to state a reason for a query. The reasons entered here were 'traffic violation' and 'investigation.'

Did the court reject the good-faith exception?

No. The opinion does not analyze good faith at all. In both the prolonged-stop section and the ALPR section it states only that the government did not identify any exception to the exclusionary rule. That is a different thing from a court considering and rejecting the argument.

Did the court say a single license plate read is a search?

No. The holding addresses the query of historical location data held in the ALPR networks. The court did not separately decide whether a single camera capturing one plate, by itself, is a Fourth Amendment search, and the opinion should not be read as resolving that question.

Does Oklahoma have a law regulating license plate readers?

Oklahoma has one plate reader statute, 47 O.S. 7-606.1, which creates the Uninsured Vehicle Enforcement Program and governs plate reader use and data for enforcement of the Compulsory Insurance Law. It is not a general warrant requirement for police plate reader queries. The Kyle opinion does not cite or construe it, and the government argued that state ALPR law is not relevant to the Fourth Amendment analysis.

What happens next in this case?

The docket shows the Opinion and Order granting the motion to suppress was entered October 1, 2026. We are not predicting any outcome. Suppression orders in federal criminal cases can be appealed by the government under limited circumstances, and we will update this page as the docket changes.