Report: 85 Percent Of Law Enforcement Agencies Will Have License Plate Readers Within The Next Five Years

Automatic license plate readers don’t pose much of a threat to our privacy if there aren’t very many of them. Like surveillance cameras, they really only become a problem when the data they collect are situated in a broader context of pervasive monitoring. One data point showing that your car drove past a stationary license plate reader on one highway doesn’t tell the government very much. But the data points begin to pile up when the surveillance cameras and license plate readers are on every street corner and police cruiser. And absent commonsense limits, that means police and prosecutors (and anyone else who gets at the database) can map your movements with the click of a button.

That’s why the ACLU has invested resources in the effort to protect our motoring privacy from unwarranted retroactive government surveillance. We didn’t want to wait until license plate readers (LPRs) were everywhere before we acted to protect our privacy; the trends seemed clear to us.

Now, a report published by the Police Executive Research Forum (PERF) shows that we were right to act early.

Writing in “How Are Innovations in Technology Transforming Policing,” a report partially underwritten by a foundation connected to the LPR manufacturer Motorola, PERF’s executive director Chuck Wesler demonstrates that police departments nationwide are eagerly acquiring the tools. Using statistics from a PERF survey distributed to hundreds of police departments in 2011, he writes:

71 percent of responding agencies already have LPRs. But typically, an agency has only a few vehicles equipped with the devices, and they are used for certain limited purposes, such as finding stolen cars or vehicles that have multiple parking violations and can be booted or towed. But our survey found that almost every police agency expects to acquire or increase their use of LPRs in coming years, and that five years from now, on average they expect to have 25 percent of their cars equipped with LPRs. [Emphasis added]

According to PERF’s survey results, most of the queried agencies without license plate reader systems plan to get them, and those that already use them plan to expand their programs:

A large majority of agencies (85 percent) plan to acquire or increase their use of LPRs during the next five years. On average, responding agencies expect that 25 percent of their vehicles will have LPRs on board in five years. [Emphasis added.]

The price of license plate reader systems is likely to fall precipitously as the technology becomes an increasingly common law enforcement fixture. It’s already fallen substantially over the past few years, after a boom in sales prompted by federal funding for the technologies to state and local police departments nationwide. Whereas years ago the tools cost upwards of $30k per system, some companies are now selling them for as little as $8k a pop.

For privacy advocates, there doesn’t seem to be much hope that we could roll back the expansion of the technology itself. But thankfully we can take simple steps to limit the privacy harms.

The most central functions license plate readers perform don’t require that agencies store captured plate information on everyone for long periods of time, enabling mass, retroactive, warrantless surveillance. In fact, police don’t need to retain any captured plate data at all in order to catch people driving stolen cars or with outstanding warrants.

A police officer from Mesa is quoted in the PERF report describing how successful the technology has been for the agency:

when LPRs were used, police were able to get over eight times as many checks, over four times as many hits, and about twice as many arrests and vehicle recoveries as when they were not using the LPR devices.

Those are pretty impressive stats, and those successes don’t require any data retention whatsoever -- making it clear that police can use the technology to great effect without needlessly violating our privacy.

PERF’s discussion on license plate readers also sheds light on a troubling facet of the post-9/11 federal funding of path-breaking law enforcement tools: policymaking-by-procurement. When local police want to get money from the feds to buy fancy new tools, they should approach the public—the people they protect and serve—before pursuing acquisitions, especially when those tools have implications for privacy. It isn’t appropriate for departments to move forward with such technologies without any public debate. Revealingly, the officer from Mesa quoted above told PERF:

In some communities there is a strong negative public reaction to the use of surveillance technologies. While we were doing [the license plate reader] study in Mesa, there was controversy throughout Arizona over the use of speed enforcement cameras on major roadways. The LPR program didn’t receive that sort of public reaction, probably because it was a much smaller program and not as many people knew about it. [Emphasis added.]

That isn’t right. The police shouldn’t be able to slip things like the introduction of powerful new surveillance technologies under our noses.

Thankfully, it appears as if we are increasingly having that debate—about license plate readers, in particular—in our cities and state legislatures nationwide. Moving from rhetoric to action, ACLU affiliates nationwide, including here in Massachusetts, will be working with state legislators in this session to pass statutes to protect our privacy from unnecessarily broad police deployments of license plate readers. (If you live in Massachusetts, you can take action to help us get there.)

Here’s to many other states joining New Hampshire and Maine in passing laws to limit the use of license plate readers in 2013, and to a future that’s a little bit more free.

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Bill in SF

Like most computer applications, license plate reading will continue to get cheaper rapidly, so getting good legislation about what they do with the data is important.

The most common justification for buying cheap license plate readers is likely to be parking enforcement - it's a lot faster than chalk-marking tires, so cities can make money by having parking enforcement officers going faster and being more accurate about who's still parked in the same place. Looking for specific license plate numbers is more of a policing application, and is a more complex decision than pure profit.


These scanners aren't being used for parking enforcement. These are data farming applications and license plates are being read similar to a grocer scanning your groceries. The same way the cash register displays your groceries' information, so do these plate scanners. Insurance, registration, DL number, address and DOB are immediately brought up on the screen. There is no need for the officer to ask for a license or registration because the information is directly linked from the DMV and their own data bank.

If for any reason you have been found guilty of speeding, reckless driving, DUI, ANY traffic or non traffic related incident, you will forever be in the system, and there will be an alarm that sounds off to alert the officer of your presence. When that alarm sounds off, the officer is immediately drawn to you because he wants to catch a criminal in the act regardless of whether or not you are actually a criminal or if you are in the act of picking up your child from school, on your way to or from the store, or running to the fast food drive thru.

Anyone who has ever been pulled over or has had any contact with law enforcement is in the databank. From your next door neighbor, to your grocery clerk, to you!

Ever wonder why you feel like being tailed home by a cop car? More than likely because you ARE being tailed home by an over zealous "law enforcement" officer seething at the opportunity to up his arrest stats.


It is not even remotely practical to think that police are "tracking" people with these readers. Even with the minimal amount of readers in service, the data is very large. These readers also read numbers off of mailbox's, signs, and most often read only partial plates. If law enforcement uses them to look for specific plate numbers to search for, lets say, a bank robber, he must enter the number and hope it hits. It is like a needled in a hay stack and is like winning the flipping lottery to actually come across a plate that cops need to assist them in "tracking" criminals. Worry more about GPS tracking then readers.

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