The Normative Case Against Automated License Plate Recognition

-- By BlaineTracy - 01 Mar 2024

Introduction

Automated license plate recognition (ALPR) technology refers to a system of cameras used to automatically scan the license plates of every vehicle that passes through the cameras’ view. This relatively new technology has become a favorite tool of state and local law enforcement agencies over the last few decades. As the number and sophistication of ALPR systems have increased, they have created a surveillance network that enables law enforcement to track the whereabouts, activities, associations, and behavior patterns of everyone who uses public roads. This surveillance is able to take place indiscriminately, collecting information not only on those suspected of criminal activity but on all drivers, and is done without requiring a warrant. Instead of discussing the underdeveloped case law concerning ALPR systems, this paper makes a normative argument based on the principles and plain text embodied in the Constitution that ALPR systems have run afoul of the government’s powers.

How ALPR Works

Unlike the more familiar traffic cameras used to capture still images of vehicles that run red lights or exceed speed limits, ALPR cameras are constantly recording. They can capture both still images and videos of passing vehicles. When the cameras automatically detect a license plate, the system logs the license plate number along with the time, date, and location of the scan into a centralized data bank. This information can be used in concert with other data archives to find the registration information of the vehicle and the biographical information of its owner. As technology advances, ALPR systems could incorporate biometric capabilities into their cameras, allowing them to scan and identify the faces of the drivers of each scanned vehicle.

An ALPR system is often composed of thousands of cameras, which can be affixed either to a stationary surface or to a mobile location, like a law enforcement vehicle. Agencies often install cameras citywide, giving law enforcement near-omniscience over public thoroughfares. The most bountiful feature of these networks for law enforcement—and the most dangerous aspect for private citizens—is the ability of a comprehensive camera system to record a vehicle’s travel from one location to another, painting a picture of the destinations people travel to and the times, days, and frequencies of their visits. By recording this information for all travelers, law enforcement can gather which people visit the same location at the same time, collecting knowledge of individuals’ associations with one another. This knowledge can include their religious and political affiliations, social life, and intimate relations.

Constitutional Problems with ALPR

The immense surveillance scheme enabled by ALPR runs into several problems with the intent and language of the Constitution. Its comprehensive capture of personal information and warrantless use run afoul of the Constitution’s protections for private citizens.

The reader cannot just take this in without wanting to know why. At least a sentence or two here to outline the argument is desirable or the reader may give up.

The First Amendment

The ability of ALPR systems to track an individual’s personal life conflicts with the First Amendment’s protections for people’s freedoms of speech and association. These protections were enshrined in the Constitution to secure, in part, the ability of individuals to share ideas and form associations unsanctioned by or critical of the government. A political dissident has the same right to communicate his ideas and form a group of likeminded compatriots as does a supporter of popular ideals. However, the dissident is much more likely to be targeted by the state for surveillance and curtailing of his activities.

How to get from reading the deliberately highly-legible registration tag on automobiles to the First Amendment is not a step you can take so blithely

ALPR use imposes a chilling effect on speech with which the government at large or law enforcement specifically disagrees. Knowledge that a speaker of unpopular ideas could give a speech at a rally or protest and have her vehicle tracked to and from the event will surely deter some individuals from civic participation. The marketplace of ideas envisioned through the First Amendment will suffer because the state may use ALPR to surveil the activities of individuals without cause or public oversight. It will likewise dampen the ability and willingness of individuals to form associations they would prefer to keep private from the eyes of the state. These consequences span beyond even political affiliations. The imposition of a comprehensive vehicle surveillance system could track the activities of people engaged in same-sex relationships, or the attendees at a mosque, or the patients and employees at an abortion clinic. All manner of personal, private activities are made the business of the state when the government has such an overwhelming system of travel surveillance.

The Fourth Amendment

The Fourth Amendment’s protection against unreasonable searches and seizures clearly targets surveillance as all-encompassing as ALPR. While the framers of the Constitution could not fathom something akin to ALPR, such an invasion of individuals’ privacy and liberty surely would have repulsed them. The Fourth Amendment’s prohibition on unreasonable searches of each individual’s person, houses, papers, and effects includes the information collected by ALPR. Recording a vehicle’s license plate and registration information and later querying the ALPR data bank to retrieve that information are both searches of an individual’s papers and effects. The scale of each ALPR network, the interconnectivity between networks and jurisdictions, and the precision with which they collect private information make these searches unreasonable.

Law enforcement’s ability to collect, search, employ, and redistribute this information without the issuance of a warrant exacerbates this constitutional problem. It amplifies the unreasonableness of the ALPR surveillance system and calls into question the rights of individuals to due process. When personal data can be gathered and used without probable cause or any formal legal sanction, it deprives the victims of this surveillance of their ability to ensure fairness and proper procedure in their treatment. Popular oversight and transparency are nonexistent in the current ALPR regime.

Improving the draft means addressing the central question. Automobiles are registered by the states, and are required to display highly-legible tags bearing the registration information. They are intended to communicate information that you do not dispute it is constitutional to require displayed. How then is there a constitutional problem with acquiring the information whose publication can be constitutionally required? You cite3 no cases of analogous holding, and I think there aren't any. So saying something more is clearly necessary.

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