Every week EFF receives emails from members of homeowner’s associations wondering if their Homeowner’s Association (HOA) or Neighborhood Association is making a smart choice by installing automated license plate readers (ALPRs). Local groups often turn to license plate readers thinking that they will protect their community from crime. But the truth is, these cameras—which record every license plate coming in and out of the neighborhood—may create more problems than they solve. 

The False Promise of ALPRs

Some members of a community think that, whether they’ve experienced crime in their neighborhood or not, a neighborhood needs increased surveillance in order to be safe. This is part of a larger nationwide trend that shows that people’s fear of crime is incredibly high and getting higher, despite the fact that crime rates in the United States are low by historical standards. 

People imagine that if a crime is committed, an association member can hand over to police the license plate numbers of everyone that drove past a camera around the time the crime is believed to have been committed. But this will lead to innocent people becoming suspects because they happened to drive through a specific neighborhood. For some communities, this might mean hundreds of cars end up under suspicion. 

Also, despite what ALPR vendors like Flock Safety and Vigilant Solutions claim, there is no real evidence that ALPRs reduce crime. ALPR vendors, like other surveillance salespeople, operate on the assumption that surveillance will reduce  crime by either making would-be criminals aware of the surveillance in hopes it will be a deterrent, or by using the technology to secure convictions of people that have allegedly committed crimes in the neighborhood. However, there is little empirical evidence that such surveillance reduces crime. 

Like all machines, ALPRs make mistakes

ALPRs do, however, present a host of other potential problems for people who live, work, or commute in a surveilled area. 

The Danger ALPRs Present To Your Neighborhood

ALPRs are billed as neighborhood watch tools that allow a community to record which cars enter and leave, and when. They essentially turn any neighborhood into a gated community by casting suspicion on everyone who comes and goes. And some of these ALPR systems (including Flock’s) can be programmed to allow all neighbors to have access to the records of vehicle comings and goings. But driving through a neighborhood should not lead to suspicion. There are thousands of reasons why a person might be passing through a community, but ALPRs allow anyone in the neighborhood to decide who belongs and who doesn’t. Whatever motivates that individual - racial biases, frustration with another neighbor, even disagreements among family members - could all be used in conjunction with ALPR records to implicate someone in a crime, or in any variety of other legal-but-uncomfortable situations. 

The fact that your car passes a certain stop sign at a particular time of day may not seem like invasive information. But you can actually tell a lot of personal information about a person by learning their daily routines—and when they deviate from those routines. If a person’s car stops leaving in the morning, a nosy neighbor at the neighborhood association could infer that they may have lost their job. If a married couple’s cars are never at the house at the same time, neighbors could infer relationship discord. These ALPR cameras also give law enforcement the ability to learn the comings and goings of every car, effectively making it impossible for drivers to protect their privacy. 

These dangers are only made worse by the broad dissemination of this sensitive information. It goes not just to neighbors, but also to Flock employees, and even your local police. It might also go to hundreds of other police departments around the country through Flock’s new and aptly-named TALON program, which links ALPRs around the country. 

ALPR Devices Lack Oversight

HOAs and Neighborhood Associations are rarely equipped or trained to make responsible decisions when it comes to invasive surveillance technology. After all, these people are not bound by the oversight that sometimes accompanies government use of technology--they’re your neighbors. While police are subject to legally-binding privacy rules (like the Fourth Amendment), HOA members are not. Neighbors could, for instance, use ALPRs to see when a neighbor comes home from work every day. They could see if a house has a regular visitor and what time that person arrives and leaves. In San Antonio, one HOA member was asked what they could do to prevent someone with access to the technology from obsessively following the movements of specific neighbors. He had never considered that possibility: "Asked whether board members had established rules to keep track of who searches for what and how often, Cronenberger said it hadn’t dawned on her that someone might use the system to track her neighbors’ movements.” 

Machine Error Endangers Black Lives

Like all machines, ALPRs make mistakes. And these mistakes can endanger people’s lives and physical safety. For example, an ALPR might erroneously conclude that a passing car’s license plate matches the plate of a car on a hotlist of stolen cars. This can lead police to stop the car and detain the motorists. As we know, these encounters can turn violent or even deadly, especially if those cars misidentified are being driven by Black motorists. 

This isn’t a hypothetical scenario. Just last month, a false alert from an ALPR led police to stop a Black family, point guns at them, and force them to lie on their bellies in a parking lot—including their children, aged six and eight. Tragically, this is not the first time that police have aimed a gun at a Black motorist because of a false ALPR hit.

Automated License Plate Reader Abuses by Police Foreshadow Abuses by Neighborhoods 

Though police have used these tools for decades, communities have only recently had the ability to install their own ALPR systems. In that time, EFF and many others have criticized both ALPR vendors and law enforcement for their egregious abuses of the data collected. 

Police abuse this technology regularly. And unfortunately, neighborhood users will likely do the same. 

A February 2020 California State Auditor’s report on four jurisdictions’ use of this tech raised several significant concerns. The data collected is primarily not related to individuals suspected of crimes. Many agencies did not implement privacy-protective oversight measures, despite laws requiring it. Several agencies did not have documented usage or retention policies. Many agencies lack guarantees that the stored data is appropriately secure. Several agencies did not adequately confirm that entities they shared data with had a right to receive that information. And many did not have appropriate safeguards for users accessing the data. 

California agencies aren’t unique: a state audit in Vermont found that 11% of ALPR searches violated state restrictions on when cops can and can't look at the data. Simply put: police abuse this technology regularly. And unfortunately, neighborhood users will likely do the same. 

In fact, the growing ease with which this data can be shared is only increasing. Vigilant Solutions, a popular vendor for police ALPR tech, shares this data between thousands of departments via its LEARN database. Flock, a vendor that aims to offer this technology to neighborhoods, has just announced a new nationwide partnership that allows communities to share footage and data with law enforcement anywhere in the country, vastly expanding its reach. While Flock does include several safeguards that Vigilant Solutions does not, such as encrypted video and 30-day deletion policies, many potential abuses remain.

Additionally, some ALPR systems can automatically flag cars that don’t look a certain way—from rusted vehicles to cars with dents or poor paint jobs—endangering anyone who might not feel the need (or have the income required) to keep their car in perfect shape. These “vehicle fingerprints” might flag, not just a particular license plate, but “a blue Honda CRV with damage on the passenger side door and a GA license plate from Fulton County.” Rather than monitoring specific vehicles that come in and out of a neighborhood via their license plate, “vehicle fingerprint” features could create a trouble drag-net style of monitoring. Just because a person is driving a damaged car from an accident, or a long winter has left a person’s car rusty, does not mean they are worthy of suspicion or undue police or community harassment.  

Some ALPRs are even designed to search for certain bumper stickers, which could reveal information on the political or social views of the driver. While they aren’t in every ALPR system, and some are just planned, all of these features taken together increase the potential for abuse far beyond the dangers of collecting license plate numbers alone. 

What You Can Tell Your Neighbors if You’re Concerned 

Unfortunately, ALPR devices are not the first piece of technology to exploit irrational fear of crime in order to expand police surveillance and spy on neighbors and passersby. Amazon’s surveillance doorbell Ring currently has over 1,300 partnerships with individual police departments, which allow departments to directly request footage from an individual’s personal surveillance camera without presenting a warrant. ALPRs are at least as dangerous: they track our comings and goings; the data can indicate common travel patterns (or unique ones); and because license plates are required by law, there is no obvious way to protect yourself.

If your neighborhood is considering this technology, you have options. Remind your neighbors that it collects data on anyone, regardless of suspicion. They may think that only people with something to hide need to worry—but hide what? And from who? You may not want your neighbor knowing what time you leave your neighborhood in the morning and get back at night. You may also not want the police to know who visits your home and for how long. While the intention is to protect the neighborhood from crime, introducing this kind of surveillance may also end up incriminating your neighbors and friends for reasons you know nothing about. 

You can also point out that ALPRs have not been shown to reduce crime. Likewise, consider sending around the California State Auditor’s report on abuses by law enforcement. And if the technology is installed, you can (and should) limit the amount of data that’s shared with police, automatically or manually. Remind people of the type of information ALPRs collect and what your neighbors can infer about your private life. 

If you drive a car, you’re likely being tracked by ALPRs, at least sometimes. But that doesn’t mean your neighborhood should contribute to the surveillance state. Everyone ought to have a right to pass through a community without being tracked, and without accidentally revealing personal details about how they spend their day. Automatic license plate readers installed in neighborhoods are a step in the wrong direction.