Are Flock Cameras Constitutional? What a New Fifth Circuit Decision Means for Texas
Flock cameras are becoming increasingly common on Texas roads.
They photograph passing vehicles, read license plates, record when and where vehicles were observed, and allow law enforcement to search that information later.
And the network is substantial. A recent Texas Tribune investigation found that more than 200 local law-enforcement agencies had data-sharing agreements with the Texas Department of Public Safety. The cameras can collect not only license plates, but vehicle make, color and characteristics such as bumper stickers. (The Texas Tribune)
Read the Texas Tribune investigation into Flock cameras in Texas
In a previous post we addressed what can happen when opposition to Flock moves from protest to physical interference—and the Texas criminal charges that may result. If you want to know about that read Think before you touch that Flock camera.
In this article we are going to address the constitutional question:
Can police search this information without getting a warrant?
For anyone charged with a crime in Texas, we now have an important answer from the United States Court of Appeals for the Fifth Circuit.
In March 2026, the Fifth Circuit decided United States v. Porter.
The court rejected a Fourth Amendment challenge to law enforcement's use of automated license plate reader information.
But the decision doesn't necessarily mean what the simplest headline might suggest.
The Fifth Circuit did not hold that every possible use of a massive automated license plate reader network will always be constitutional.
And that's where the issue gets interesting.
The Fourth Amendment Problem
The Fourth Amendment protects against unreasonable searches and seizures.
Traditionally, however, courts have said that you generally don't have a reasonable expectation of privacy in something you knowingly expose to the public.
Your license plate is a good example.
If you drive down Interstate 35 through Waco, hundreds of people can see your vehicle and license plate.
A police officer sitting beside the highway can see it too.
So why should it matter if a camera sees it?
That's essentially the government's argument.
But critics of automated license plate readers say that asks the wrong question.
The issue isn't necessarily:
Can a police officer look at my license plate?
Of course the officer can.
The harder question is:
Can the government use thousands of cameras to collect my vehicle's location over time, store those observations in a database, and then search my past movements whenever it wants?
Those are very different forms of surveillance.
Flock itself takes the position that this distinction does not make its system unconstitutional. The company argues that its cameras create discrete, point-in-time observations of vehicles in public rather than continuously tracking a person's location in the manner of GPS or cell-site data. (Flock Safety)
Read Flock Safety's position on ALPRs and the Fourth Amendment
Technology Changes What Police Can Learn
Consider the difference.
A police officer happens to see your car outside a restaurant at 7:30 Tuesday night.
There is probably nothing constitutionally significant about that.
Now imagine a searchable database showing your vehicle:
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leaving your neighborhood Monday morning;
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arriving near your office;
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appearing near a doctor's office Tuesday;
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traveling to another city Wednesday;
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appearing near a church Thursday;
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returning home every evening;
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visiting the same residence every Saturday.
No individual observation necessarily tells the government very much.
Collectively, however, the observations could reveal quite a bit about your life.
That's why the constitutional debate over Flock cameras isn't really about license plates.
It's about aggregation.
And the possibility of misuse isn't entirely theoretical. A 2026 Washington Post investigation identified numerous cases in which law-enforcement personnel were accused of using Flock or other license-plate-reader systems for unauthorized personal purposes, including tracking spouses, girlfriends and former partners. (The Washington Post)
Read the Washington Post investigation into misuse of license-plate readers
Following increased scrutiny, Flock announced additional safeguards, including requiring criminal case numbers for searches, automated review for abnormal activity and a reduction in its default data-retention period. (The Washington Post)
The Supreme Court Has Already Confronted Similar Technology
Two United States Supreme Court decisions are particularly important to understanding the argument.
United States v. Jones
In United States v. Jones, police physically attached a GPS tracking device to a vehicle and monitored its movements.
The Supreme Court concluded that the government's conduct constituted a search.
Although Jones involved the physical placement of a GPS device—which is different from roadside cameras—the case became an important part of the constitutional debate surrounding technologically enhanced location tracking.
Carpenter v. United States
The more important modern comparison may be Carpenter v. United States.
There, the government obtained historical cell-site location information that allowed investigators to reconstruct substantial portions of a person's movements.
The Supreme Court held that obtaining that information constituted a Fourth Amendment search and generally required a warrant.
That was significant because much of the information concerned movements outside the home.
The Court recognized something important:
Technology can change the constitutional significance of location information because of its scale, persistence and ability to reconstruct the past.
That principle sits at the center of the Flock debate.
Enter United States v. Porter
In United States v. Porter, the defendant challenged law enforcement's use of license plate reader cameras to locate his vehicle.
Police in Gautier, Mississippi, received an LPR alert concerning a vehicle associated with Porter, who had an outstanding aggravated-assault warrant. An officer confirmed the vehicle's connection to Porter and conducted a traffic stop. A firearm equipped with a machinegun conversion device was subsequently discovered. (Justia Law)
Porter argued that he had a reasonable expectation of privacy in his location and movements and that police needed a warrant before obtaining the vehicle-location information.
The Fifth Circuit disagreed.
On March 17, 2026, the court held that the particular use of LPR technology before it did not constitute a Fourth Amendment search.
For criminal cases in Texas federal courts, that is now an extremely important precedent.
But we need to look at why the court reached that conclusion.
The Scale of the Surveillance Mattered
The system considered in Porter was relatively limited.
The police department had approximately ten LPR camera locations. The system did not continuously follow Porter's vehicle everywhere it traveled. Instead, it generated periodic observations when the vehicle passed one of those cameras.
The Fifth Circuit considered that important.
It distinguished the system from the extensive cell-phone location history involved in Carpenter. In the court's view, the LPR information before it was closer to observing someone's movements along public roads than creating the sort of comprehensive location history that concerned the Supreme Court in Carpenter. (Justia Law)
That factual limitation may become extremely important as Flock networks grow.
So Does Porter Mean Flock Cameras Are Constitutional?
Not necessarily in every situation.
It would be easy to summarize Porter as:
"The Fifth Circuit says Flock cameras don't violate the Fourth Amendment."
That's too broad.
A more accurate statement is:
The Fifth Circuit held that the particular use of license plate reader information presented in Porter did not constitute a Fourth Amendment search.
Imagine two very different cases.
Scenario One
Police investigating a robbery know the suspect vehicle's license plate.
They search recent camera records and discover that the vehicle passed one camera near the scene of the crime.
Scenario Two
Police search a regional or nationwide network covering 30 days and retrieve dozens or hundreds of sightings showing where a person's vehicle traveled, where it regularly stopped and patterns revealing substantial portions of that person's daily life.
Are those constitutionally identical?
That question is considerably harder.
Norfolk, Virginia Shows How Different the Facts Can Become
A pending constitutional challenge involving Norfolk, Virginia illustrates the problem.
Norfolk's police department operates 176 Flock cameras. The department also has access to data from 43 additional Flock cameras operated by third parties within the city. (Justia Dockets & Filings)
Compare that with the roughly ten camera locations involved in Porter.
Norfolk's cameras operate around the clock and record license plates as well as vehicle make, type, color and distinguishing features such as roof racks and bumper stickers. (Justia Dockets & Filings)
Residents challenged that system in Schmidt v. City of Norfolk, arguing that the network permits police to reconstruct their movements without obtaining a warrant.
The federal district court ultimately ruled for Norfolk in January 2026. That decision is now being challenged in the Fourth Circuit Court of Appeals.
Read about the Schmidt challenge to Norfolk's Flock network
The contrast between Porter and Schmidt illustrates what may become the critical constitutional issue.
Ten cameras producing occasional observations are one thing.
Hundreds or thousands of interconnected cameras capable of creating a historical picture of someone's movements may be something very different.
How Much Surveillance Is Too Much?
This is likely to become one of the major issues in future ALPR litigation.
Courts may eventually have to consider factors such as:
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how many cameras were searched;
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how many vehicle sightings were retrieved;
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how long a period was examined;
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how geographically extensive the search was;
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whether multiple police agencies shared their data;
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whether privately operated cameras were included;
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whether the search reconstructed a person's regular movements;
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whether it revealed visits to sensitive locations;
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whether officers repeatedly monitored the same vehicle.
At some point, a defendant will argue that the system has moved from merely observing a vehicle in public to reconstructing someone's life.
Where that constitutional line falls remains an important question.
And it is no longer merely an academic debate.
Public resistance to the technology has increased substantially. In August, Governor Greg Abbott directed Texas state agencies to halt state funding for Flock cameras amid scrutiny of the network. A Texas Tribune investigation found that at least $30 million in state funding had helped build the system and identified at least 3,200 cameras connected with that funding. (The Texas Tribune)
Read the Texas Tribune investigation into Texas funding for Flock cameras
The Constitutional Question Isn't Finished
For now, United States v. Porter gives law enforcement an important victory in the Fifth Circuit.
Limited use of automated license plate reader information does not automatically constitute a Fourth Amendment search.
But technology isn't standing still.
Camera networks are growing. Agencies can share information. Search capabilities are becoming more sophisticated. And the amount of historical vehicle-location information available to police continues to increase.
The national debate is growing as well. A Reuters/Ipsos poll released this week found substantial public division over Flock cameras as Texas and other states reconsider aspects of their use. (Reuters)
Eventually, courts may have to answer a question that Porter does not completely resolve:
When does a collection of public observations become a comprehensive record of a person's movements?
That may ultimately be the most important constitutional question surrounding Flock cameras.
Coming Next: Can Police Stop You Because of a Flock Alert?
Even if police can search Flock records without obtaining a warrant, that doesn't necessarily mean they can stop every vehicle identified by the system.
In the next installment, we'll examine whether a Flock camera hit provides reasonable suspicion for a traffic stop, what happens when the system gets a plate wrong, and how defense lawyers can challenge the evidence used to justify the seizure.
This article is provided for general educational purposes and is not legal advice. Every criminal case depends upon its individual facts.
The controversy has produced another development: people have begun damaging or interfering with Flock cameras. That creates an entirely different legal problem.
