By: James Matlock
Across the United States, a quiet infrastructure of automated license plate reader (ALPR) cameras—dominated by companies like Flock Safety—has proliferated, photographing vehicles, extracting plate numbers, vehicle characteristics (make, model, color, distinguishing features), timestamps, and locations, then uploading the data to searchable cloud databases. With deployments exceeding 100,000 cameras in thousands of communities, these systems generate billions of scans monthly. Law enforcement can query the data without warrants in many cases, often with national or statewide lookup capabilities that turn local collections into a near-nationwide tracking network.
This is not targeted policing. It is suspicionless, continuous collection of the movements of ordinary people going about lawful activities. The constitutional problems are profound under the Fourth Amendment, which protects the right of the people to be secure against unreasonable searches. When layered with emerging vehicle technologies that can limit operation and the explosive growth of data centers needed to store and process this volume of location data, the system threatens not only privacy but the practical freedom of movement itself.
The Constitutional Core: From Public Roads to a Mosaic of Life
Traditional doctrine holds that there is no reasonable expectation of privacy in a license plate visible on a public road. Courts have long allowed officers to observe and record what is in plain view. Flock and similar systems exploit this principle at industrial scale. Cameras capture every passing vehicle, retain data (typically 30 days by default, though configurable), and make it instantly searchable by plate, partial plate, or vehicle attributes across jurisdictions.
The Supreme Court’s decision in Carpenter v. United States (2018) recognized that prolonged collection of location data—there, cell-site location information—can reveal the “whole of [a person’s] physical movements” and therefore constitutes a search requiring a warrant. The “mosaic theory” holds that discrete public observations, aggregated and retained, can reconstruct intimate details of life: medical visits, religious attendance, political associations, relationships, and daily routines. Critics of Flock systems, including the Institute for Justice and ACLU, argue that dense ALPR networks achieve precisely this result. In one Norfolk, Virginia case, plaintiffs’ vehicles were logged hundreds of times over months.
Courts have split. Some rulings (including a January 2026 district court decision in Schmidt v. City of Norfolk and certain appellate decisions) have upheld limited deployments, emphasizing that discrete snapshots with gaps do not yet amount to continuous tracking equivalent to Carpenter. Judges have noted, however, that density and retention matter: at some point the network becomes intrusive enough to cross the constitutional line. Appeals are pending, and denser systems (such as San Jose’s hundreds of cameras) face fresh challenges. A recent Supreme Court ruling treating geofence warrants as searches has strengthened arguments that dragnet location collection requires judicial oversight.
The practical reality is a system designed for broad access. National lookup features have allowed agencies far from the collecting jurisdiction—including federal entities—to query local data, sometimes without the full knowledge or consent of the local governments that paid for the cameras. Abuses documented by researchers include searches tied to protest activity, reproductive healthcare travel, and other sensitive matters. The architecture itself enables suspicionless retrospective surveillance of the innocent majority.
Texas’s Rejection of Red-Light Cameras: A Precedent Against Automated Camera Enforcement
Texas provides a clear political and legal precedent against automated photographic enforcement. In 2019, the Legislature passed House Bill 1631, signed by Governor Greg Abbott, prohibiting municipalities from operating “photographic traffic signal enforcement systems” (red-light cameras) and barring citations based on recorded images. Existing contracts were largely allowed to expire; the systems were phased out. The ban reflected widespread public opposition rooted in concerns over privacy, accuracy, due process, revenue motives, and the principle that enforcement of traffic laws should involve human judgment rather than automated systems.
Red-light cameras were far narrower than modern ALPR networks—they targeted specific intersections for specific violations. Flock-style systems photograph vehicles continuously across entire road networks for general investigative use, with data shared far more broadly. Texas’s rejection of the more limited technology underscores the state’s traditional skepticism toward camera-based systems that operate without individualized suspicion or immediate human involvement. Yet ALPR deployments have expanded significantly in Texas, including by local agencies and the Department of Public Safety on state rights-of-way, prompting local pushback, contract terminations in some jurisdictions, and public controversy.
The inconsistency is striking: a state that outlawed automated ticketing cameras has allowed the growth of a far more comprehensive vehicle-tracking grid.
Vehicle “Kill Switches” and Control Over Free Movement
Freedom of movement—the ability to travel without arbitrary government restraint—is a fundamental liberty interest, deeply rooted in Anglo-American tradition and protected by constitutional principles including the Privileges or Immunities Clause, Due Process, and the right to travel recognized in case law. Mass location surveillance already chills this liberty by creating a permanent, searchable record of where people go. Emerging vehicle technologies raise the stakes by potentially enabling physical control.
Section 24220 of the Infrastructure Investment and Jobs Act (2021) directed the National Highway Traffic Safety Administration to issue a federal motor vehicle safety standard requiring new passenger vehicles to be equipped with “advanced drunk and impaired driving prevention technology.” The statute defines this as a system that can passively monitor driver performance to identify possible impairment and “prevent or limit motor vehicle operation if an impairment is detected.”
It has been note that the law does not create a remote government “kill switch” under direct law-enforcement or bureaucratic control, nor does it currently mandate external access. As of 2026, NHTSA has not finalized the implementing rule, and commercially ready systems meeting the statutory criteria remain limited. Critics, including members of Congress, nonetheless argue that embedding systems capable of disabling or limiting vehicle operation—especially in vehicles that increasingly communicate with external networks—creates infrastructure that could later be expanded, regulated, or accessed in ways that constrain movement. Combined with persistent location tracking, the capacity to know where every vehicle has been and the technical ability to limit its operation represents a qualitative shift in the state’s potential power over physical liberty.
Even without immediate remote government control, the convergence is concerning: comprehensive records of movement plus onboard systems that can intervene in vehicle operation. Historical experience with surveillance technologies shows that capabilities, once built, tend to expand in use and purpose.
Data Centers: The Invisible Backbone of Persistent Surveillance
None of this scale is possible without massive data infrastructure. Flock systems transmit images and extracted metadata over cellular networks to cloud storage, primarily Amazon Web Services (including GovCloud environments for compliance with Criminal Justice Information Services standards). Data is encrypted, subject to retention policies (commonly 30 days rolling deletion enforced by lifecycle rules), and made searchable.
The broader explosion of data-center construction—driven by AI, cloud computing, and hyperscale demand—provides the physical capacity to ingest, store, index, and analyze the continuous stream of vehicle observations from tens or hundreds of thousands of cameras. Surveillance systems generate enormous volumes of structured location data and imagery; AI-enhanced analysis (vehicle fingerprinting, pattern detection) multiplies the computational and storage burden. Data centers are not neutral warehouses; they are the essential engines that turn ephemeral public observations into durable, queryable intelligence.
As camera density increases and retention or sharing expands, the storage and processing demands grow. The same infrastructure supporting commercial AI and cloud services underpins the technical feasibility of nationwide vehicle tracking. Without this backend, the “national lookup” architecture would collapse under its own data weight.
Implications and the Path Forward
Taken together, these elements form a surveillance architecture that is difficult to reconcile with constitutional limits on government power. Warrantless, suspicionless collection and retention of movement data at population scale tests the boundaries of the Fourth Amendment under the Carpenter framework. Texas’s explicit legislative rejection of red-light cameras demonstrates that democratic majorities can and have drawn lines against automated camera enforcement when privacy and fairness concerns predominate. Vehicle systems capable of limiting operation raise the prospect of converting knowledge of location into physical restraint. Data-center expansion supplies the industrial-scale storage and computation that make the entire system viable.
Defenders emphasize crime-solving benefits—stolen vehicle recovery, suspect identification, missing persons—and note that plates are public and retention is time-limited. Those benefits are real in individual cases. The constitutional question, however, is not whether useful evidence can be obtained, but whether the government may construct a comprehensive, retrospectively searchable record of the movements of the entire driving public without individualized suspicion or judicial authorization. Scale changes the constitutional analysis.
Possible responses include legislative restrictions on retention periods, data sharing, and national lookups; warrant requirements for historical queries beyond short windows; transparency mandates; and, in jurisdictions that have already rejected red-light cameras, parallel scrutiny of ALPR systems. Courts will continue to grapple with the tipping point at which discrete public observations become an unconstitutional mosaic. Citizens and local governments retain the power to reject or terminate contracts, as dozens of communities have already done.
The right to move freely without the government compiling a detailed, searchable dossier of one’s travels is not a technicality. It is a core aspect of ordered liberty. Flock-style systems, vehicle intervention technologies, and the data-center capacity that sustains them collectively press against that liberty. Constitutional limits exist precisely to prevent the accumulation of such power, however gradually or beneficially it is introduced.
A republic, if you can keep it.
Benjamin Franklin
September 18, 1787
