A federal judge in Tulsa has ruled that a sheriff's deputy carried out an unconstitutional search when he pulled a month of a driver's location history from license plate reader databases, including Flock Safety's, without a warrant. In an opinion signed on October 1, U.S. District Judge Sara E. Hill of the Northern District of Oklahoma described the networks as "a type of indiscriminate mass surveillance" and suppressed the evidence. According to the criminal complaint, that evidence includes about 44.5 kilograms of suspected methamphetamine.
The ruling runs against most of the case law, and the opinion says so itself. Three weeks earlier, on September 10, a federal judge in Los Angeles reached the opposite conclusion in United States v. Riley, holding that plate reader "database queries are not searches within the meaning of the Fourth Amendment." Judge Hill acknowledged that "nearly every court examining the issue to date" has ruled the way the Los Angeles court did, including three other federal courts in Oklahoma, one of them in her own district. A district judge's ruling binds no other court.
The ruling is also narrower than its headlines. Judge Hill threw the evidence out on two independent grounds, and the plate reader holding was the second. She first found that the deputy kept the driver detained without legal justification after the traffic stop was over, which on its own was enough to suppress everything found in the car. And the opinion concerns a look back through weeks of stored location history. It does not address real-time alerts, such as a hit on a plate listed as stolen or wanted.
Flock, which was not a party to the case, said in a statement to 404 Media: "Flock was not a party to this case. The ruling goes against the overwhelming weight of authority in similar cases across the country, including multiple recent decisions in Oklahoma, and we expect it will be appealed and ultimately overturned. This ruling is limited to the specific facts of this case. It does not set controlling precedent and does not affect law enforcement agencies' continued use of these important public safety technologies." Michael Soyfer, a lawyer at the Institute for Justice, which is suing over Norfolk, Virginia's Flock network in a separate case, told the same outlet that the opinion "recognizes one thing that courts ignore which is the sheer breadth of these systems."
What happened on the highway
The account below is the court's, from findings made after an evidentiary hearing on August 27, unless it is attributed to someone else.
On the evening of May 10, Tulsa County Deputy Sheriff Freddie Alaniz, a highway drug-interdiction officer who has served as a task force officer with the Drug Enforcement Administration, was parked beside the highway watching traffic. A rented Mazda SUV with California plates went by, and the camera on his patrol car logged its plate. The judge found that he pulled out to follow it "for no apparent reason other than the fact that it had a California license plate," and ran the plate through two plate reader databases, Flock and one called VehicleManager. Both systems ask officers to give a reason for a search. He entered "traffic violation" and "investigation." At the time, the judge found, "all Alaniz knew was that the vehicle had a California license plate."
The results showed the car had driven from Locust Grove, Oklahoma, to the area where California meets Arizona and was heading back toward Missouri after a short stay. In all, the deputy had access to a month of the car's location records: more than 50 sightings across several states.
He then watched the driver, Melisa Kyle, follow another car at about 30 feet, and pulled her over. The judge held that this stop was lawful, because the following distance alone gave him an objectively reasonable basis for it. He questioned Kyle about her trip, wrote her a warning and handed back her license. He then asked to search the car. She said no, and he told her she was being detained so his dog could sniff the vehicle. The dog alerted.
According to the federal criminal complaint, deputies found bags of a white crystal-like substance packed with dryer sheets in three suitcases, along with a digital scale and bundles of cash in a locked box. The complaint gives the package weight, before laboratory analysis, as 44,528.8 grams. A grand jury indicted Kyle on one count of possession of methamphetamine with intent to distribute. She has not been convicted. The complaint, sworn by a DEA task force officer two days after the arrest, describes the stop as being for improper lane-change signals and does not mention the plate reader searches. Such affidavits say on their face that they are meant only to show probable cause and do not set out everything the officer knows.
Two separate reasons the evidence was thrown out
The detention. Under the Supreme Court's 2015 decision in Rodriguez v. United States, once a traffic stop's purpose is complete, police may hold a driver longer only if they have reasonable suspicion of some other crime. The government offered six reasons: the short trip to California and Kyle's account of it, the amount of luggage, a cigarette she lit, the rental car, and her nervousness. The deputy testified that his training and experience taught him that people who make very short trips to California and come straight back are usually moving drugs. Judge Hill took each factor in turn. She gave the luggage "a small amount of weight" and the rest little or none, and she found that the deputy never explained what in his training made these particular facts suspicious. Taken together, she wrote, they were "the same type of circumstances that everyday Americans encounter on long road trips for many legitimate reasons." Kyle's mention of marijuana in the car came after he announced she was being detained, so it could not count. "Facts learned later in the investigation are irrelevant," the opinion says, quoting the federal appeals court for the Tenth Circuit, which covers Oklahoma. The same rule explains why the drugs reported in the complaint play no part in the analysis: a search is judged by what the officer knew before it, not by what it turned up.
The plate reader search. The government's position was that a license plate on a public road is in plain view, so no one can reasonably expect privacy in it. That argument rests on United States v. Knotts (1983), in which the Supreme Court held that a person driving on public roads "has no reasonable expectation of privacy in his movements from one place to another." Judge Hill wrote that other courts "give too much weight" to that language. Knotts involved a single radio beeper hidden in a single container, and the Court in Knotts itself said that if "dragnet type law enforcement practices" ever arrived, "there will be time enough then to determine whether different constitutional principles may be applicable." Her conclusion was that the time has come: "this Court is now faced with technology that appears to be approaching the dragnet type law enforcement practice Mr. Knotts warned of."
She relied instead on Carpenter v. United States (2018), which held that obtaining historical cell-site records is a search, and on this June's Chatrie v. United States, which held the same for a geofence warrant seeking phone location history. Both rest on the principle that people "have a reasonable expectation of privacy in the whole of their physical movements." She conceded the obvious difference: a plate reader record "is not the same fine-tuned level of detail that something like a cell phone reveals." But she held that a month of records drawn from a network that logs every passing car crosses the line:
"By virtue of how ALPR technology works, Alaniz and other officers using these systems have access to a continuously updated location history for all vehicles caught on ALPR cameras within the network. This is a type of indiscriminate mass surveillance. It is not targeted on a single individual, as in Carpenter."
Because the only reason for the search was an out-of-state plate, it lacked probable cause, and everything after it was suppressed as "fruit of the poisonous tree." The opinion says the government did not identify "any adequate exception to the exclusionary rule" that would have saved the evidence.
Why two federal judges came out opposite ways
The Los Angeles ruling and the Tulsa ruling involved very different searches. In Riley, police investigating two kidnappings queried the Flock cameras of two California cities and obtained "four photographs each of the whereabouts of the defendant's car," according to a summary by the law professor Orin Kerr. Judge Virginia A. Phillips found that searches like those were "clearly distinguishable from and less extensive than the 'near perfect surveillance'" at issue in Carpenter. In Kyle, the search returned a month of history, more than 50 sightings across several states, and it was run on nothing more than a California plate.
That difference does not fully reconcile the two rulings, because the Los Angeles court framed its holding broadly: database queries, as a category, are not searches. The Tulsa court framed its holding around the scale of the network. Which approach the appeals courts adopt will decide how far either ruling reaches.
The case for the other side
The government's argument is the one most courts have accepted, and it is not a technicality. The Fourth Amendment has long left unprotected what a person openly exposes to the public, and a license plate exists so that it can be read in public. According to Judge Hill's own opinion, three federal courts in Oklahoma held in the past fourteen months that plate reader use is not a search: United States v. Acosta (N.D. Okla., August 2025), United States v. Brown (W.D. Okla., August 2025) and United States v. Schoggins (E.D. Okla., January 2026). In January a federal judge in Virginia granted judgment to the City of Norfolk in the leading civil challenge, finding the plaintiffs had not shown that its 176-camera Flock network could track the whole of a person's movements.
There is a practical case too, and Judge Hill acknowledged that the technology "comes with remarkable benefits." Flock says its systems supported about a million investigations last year and helped locate more than 10,000 missing people. Independent research is more qualified. One evaluation found that expanding plate reader coverage was associated with fewer shootings, vehicle thefts and property crimes, but not with less violent crime overall. A warrant requirement for look-back searches would not switch the cameras off, but it would add a step before every query like the one the deputy ran.
The Tulsa ruling is not the first of its kind, but it appears to be the first by a federal court. In May 2024 a state judge in Norfolk, Virginia, suppressed Flock evidence in a robbery case (Commonwealth v. Bell), holding that "the collection and storage of license plate and location information by the FLOCK system constitutes a search within the meaning of the Fourth Amendment and should require a warrant."
What comes next
The trial set for October 6 has been cancelled, and Judge Hill set a status conference for October 5. A defense motion to release Kyle from detention, which the docket describes as unopposed, is set for a hearing the same day. As of October 4 the docket showed no appeal. Federal law (18 U.S.C. § 3731) allows the government to appeal a suppression order to the Tenth Circuit within 30 days. To get the evidence back, prosecutors would have to win on both grounds: even a ruling that plate reader queries are not searches would leave the unlawful-detention finding in place. The Tulsa County Sheriff's Office and the U.S. Attorney's Office for the Northern District of Oklahoma had not commented publicly in any of the coverage reviewed for this article.
The larger test is in Virginia. The Fourth Circuit has tentatively scheduled argument in the Norfolk case, Schmidt v. City of Norfolk, for the week of December 8, according to Jeffrey Welty of the University of North Carolina School of Government. The Justice Department and sixteen states plus the District of Columbia have filed in support of the city. Groups ranging from the Cato Institute to the ACLU have filed in support of the residents. A ruling from a federal appeals court would bind every district court in its circuit, something none of the Flock rulings so far can do.
For now the count is lopsided: one federal district judge on one side, most of the courts that have ruled on the other, and the Fourth Circuit's argument in the Norfolk case still two months away.
Primary documents: the opinion (38 pages), the criminal complaint and the indictment. All three, along with the earlier rulings named here, are in Profoundd's Flock and plate reader source archive.