Applying AI to License Plate Surveillance

License plate scanners aren’t new. Neither is using them for bulk surveillance. What’s new is that AI is being used on the data, identifying “suspicious” vehicle behavior:

Typically, Automatic License Plate Recognition (ALPR) technology is used to search for plates linked to specific crimes. But in this case it was used to examine the driving patterns of anyone passing one of Westchester County’s 480 cameras over a two-year period. Zayas’ lawyer Ben Gold contested the AI-gathered evidence against his client, decrying it as “dragnet surveillance.”

And he had the data to back it up. A FOIA he filed with the Westchester police revealed that the ALPR system was scanning over 16 million license plates a week, across 480 ALPR cameras. Of those systems, 434 were stationary, attached to poles and signs, while the remaining 46 were mobile, attached to police vehicles. The AI was not just looking at license plates either. It had also been taking notes on vehicles’ make, model and color—useful when a plate number for a suspect vehicle isn’t visible or is unknown.

Posted on August 22, 2023 at 7:04 AM26 Comments


John Tillotson August 22, 2023 7:30 AM

It does amaze me to see the amount of personal data that is grabbed by the surveillance platforms every time that a user visits a website (financial info, browsing history, PII, voice and typing data, etc), and that merits not a whimper, even though the browsing is done inside a home in a place where privacy is expected, and on a “personal” computer where we might expect our data to be private.

But people freak out over a limited license plate scanning program that only tracks and aqgregates publicly-visible information in a public space where no realistic expectation of privacy exists.

This might be a really valuable tool for law enforcement, with the ability to correlate vehicle traffic to crimes, finding stolen cars, finding stolen license plates and helping with Amber Alerts. Clearly it has the ability to reduce costs and improve efficiency.

People worried about privacy need to get their priorities straight.

Winter August 22, 2023 9:34 AM

@John Tillotson

This might be a really valuable tool for law enforcement, with the ability to correlate vehicle traffic to crimes, finding stolen cars, finding stolen license plates and helping with Amber Alerts.

Is this not the definition case of “dragnet surveillance”? You are surveiling random people for future indictment without cause.

Gordon Shumway August 22, 2023 10:20 AM

@John T.

While I agree many more harms go unnoticed, I think there’s an aspect of this system you’re missing – It’s run by a private company which doesn’t have the constraints and transparency requirements of a government entity.

In the linked Forbes article, it mentions the ALPR company, Rekor, is partnering with companies like McDonalds to use its data to customize pricing.

Is Rekor using data from public infrastructure (traffic cameras) to enhance its commercial surveilance product? It’s not clear from the article, but I’d be surprised if they weren’t.

Imagine the aggregate harm if Rekor and all its competitors are selling the data gleaned from all its sources, public and private, to aggregators like Oracle, LexisNexis, credit agencies, etc.

Such aggregation effectively represents 24/7 surveilance of the entire population. Your browser can only see what you do online, systems like this can potentially aggregate that with everything you do in the real world.

Clive Robinson August 22, 2023 10:38 AM

@ John Tillotson

“This might be a really valuable tool for law enforcement,”

Going back over 2years?

“But people freak out over a limited license plate scanning program that only tracks and aqgregates publicly-visible information in a public space where no realistic expectation of privacy exists.”

Actually there are atleast two types of privacy expected in a public place,

1, Not to be subject to unlawful surveilance.
2, Ephemerality of public vision.

If you were to stand outside a school taking pictures of every child that went in or came out, you would fairly quickly find that nobody is likely to agree with your “no realistic expectation of privacy exists”. In fact it would be likely the Police would take you and your equipment away at the minimum for “creating a nuisance”, and anything else they could. An application to a Judge would probably get a warrant to not just search your home but cease all your electronic equipment and chances are you won’t get it back, especially as any half baked prosecuter could get you found guilty of some crime.

But people “don’t remember” that is what they see is ephemeral, and their is a societal expectation this should be so for good and proper reasons.

At the very least we know US Politics is scummy and campaigns are run in part by muck rakers to put it politely.

One of the dangers of video and other recordings that are de facto surveillance is that things can be used to distort perception. Anyone who has access to any kind of non consensual recordings of others gains power over them in ways few can imagine.

So all these recordings should be deleated within a very short period of a few days.

From what was reported about the lawyer’s words they were correct and the Police are using the technology not just unlawfully but without due cause,

“With no judicial oversight this type of system operates at the caprice of every officer with access to it.”

But it’s not just Police Officer’s with access, read down and you will find it’s anyone with money can get access. Ask yourself how long it is before we hear that the kid in the drive through has aquired details and passed them on to others either for gain or out of fear?

But the lawyer raised an important point in his motion to suppress,

“Given the vast nature of the ALPR network and the need to travel public highways to engage in modern life,”

“avoiding ALPR surveillance is both unfeasible, if impossible.”

And what he did not mention, is that now such surveillance is at the very least perpetual if not eternal. This is something society as we currently know it can not survive.

iAPX August 22, 2023 1:26 PM

The problem comes from both Storage + AI Identification or pattern matching, the worst problem being the storage itself, wether it cames from AI curated entries or worse everything stored and then using AI on that huge amount of videos.

For example, having an AI that analyze live video stream for bad behaviours and/or plates of declared stolen vehicles seems correct for me.

Naturally you have to store only the matching video parts, temporarily (for days not weeks or months) to have these videos validated by policemen, and eventually only those approved to be kept on file by the police.
Never any access to the video for the privately held third part.

What they seems to do is very different, as they store the video first, turning into an effective mass surveillance tool, owned, operated and with full access by a privately held company.

Permanence of surveillance, permanence of storage, undisclosed and uncontrollable intents, including commercial interest to resell the PII: this is everything but someone taking naive photographs for itself.

Ted August 22, 2023 1:33 PM

In US v. David Zayas, it’s interesting that as of Nov 2022:

The Court DENIES (i) a hearing to allow Defendant to challenge facts gathered in the WCPD’s investigation through the adversarial process;

Does this mean the ALPR data will be allowed as evidence in the case? Or that it was not considered overbroad “dragnet surveillance”?

lurker August 22, 2023 2:23 PM


You are surveiling random people for future indictment without cause.

I can allow for non-native spekers of English, but nowadays I am seeing sentences like this from native born fluent English speakers.

“indictment without cause” is beyond Kafka-esque.

Is “surveiling random people without cause” the definition of “dragnet surveillance”? Surveiling random people in order to find causes for future indictment might be seen by some LEAs as an efficient use of their resources to maintain a law-abiding community.

The problem seems to be how to reconcile such surveillance with the Constitutional rights (if any) of the populace.

My Probation Officer and FBI Know Who I Am August 22, 2023 3:02 PM

…and you can bet your butts that it too, will be added to the LE’s and IC’s “toolbox”
courtesy ht tps:// … because, ya know, it can’t hurt to have yet another valuable piece of our lives available to the highest bidder at the push of a button or a mouse-click away, or a voice-command away… because, hey, public realm, but you can always feel free to stay home/inside and be tracked online, your choice.
You know what they say: “if you’re a law abiding citizen – you’ve got nothing to worry about” (sarcasm intended). Right? A step closer to the mighty micro chip implant with built-in GPS.

Joe Everyone August 22, 2023 3:46 PM

We can all agree that it’s a good thing to use AI to catch “bad guys” like drug dealers and murderers based on their driving habits. Technology will keep us all safe. We could also lower the cost of healthcare by denying access to those who spend too much time at fast food drive-through windows or parked too long in front of bars. Health insurance would finally become more affordable, if we just watched those sorts of people more closely. We should also deny loans and employment to people who spend too much time parked at churches, health clinics, or any other place that isn’t like us. And this is especially true for people found to be driving to visit psychiatrists, psychologists or counselors because those people are unstable and cannot be trusted like we can. Those people probably shouldn’t even be allowed to drive in the first place. Total surveillance only affects those people who have something to hide, after all.

Clive Robinson August 22, 2023 4:20 PM

@ My Probation Officer…, ALL,

Re : Ideas you forment.

“A step closer to the mighty micro chip implant with built-in GPS.”

But how will it be done?

All the nonsense over vaccinations showed that the cost of giving everyone the needle in the US would be prohibitive, and a considerable number of people would not have it done…

So the casual thought about Smart Phones being,

“The bugging device you pay for”

Sparked an idea… A lot of people will at some time put their mobile phone in their trouser or equivalent pocket…

The US managed to force GPS chips into most phones that go world wide.

Could the US force some other item into a mobile phone?

Yes… How about being able to have an auto injector built into a phone kind of like those emergency pen injectors for people with life threatining allergies, such that when you put it in that pocket it fires the chip right in to your muscle a kind of “One and Done” solution…

As they say “Just a thought on your idea” 😉

I don’t think so buddy boy August 22, 2023 6:12 PM

@Joe Everyone,
You say: “we can all agree” blah blah blah…
Please do not say anything along those lines ever again because it’s extremely inappropriate.

Please find a hobby or someone to talk to, perhaps someone outside your routine circles, someone who’s not in your church or family, so you can broaden your horizons, meet new people, learn new things and ways. Or just get a dog, eh? The brush you paint with is too wide, may we, you and I, never cross paths, it would take too much time and effort with you and it would be a waste of my time. Please, don’t include other people, especially not me, in your judging everyone and everything that is not in your spitting image. Thank you very much.

Random Nobody August 22, 2023 6:55 PM

@Joe Everyone
I commend you for painting the picture we all need to see.

In case you don’t understand, he is taking this tech and the justifications given all the way to its logical end to demonstrate how this will be abused. Sarcasm is hard to infer when reading.

C U Anon August 22, 2023 7:38 PM

@I don’t think so:

Read Joe Everyone from the top down.

First off the handle is a “micky take” on a cartoon pastiche of a “red neck republican” beer swiller on his second or third six pack venting his spleen.

Then we get into roughed up nonsense that would typically be spewed up in a cartoon of such a red neck blaiming the world for the actual behaviours voting a certain way gets everyone.

Finally you get the traditional security “dog whistle” that’s probably older than all the readers here (old enough that Goodwin’s law might be invoked).

In short it’s sarcasm mixed with irony and written in a way to initially “get the goat” / “raise the dander” / “be a wind up”. Then claim by claim become more ludicrously reworks of political “dog whistles”.

In the process it’s also cautionary because those “dog whistles” or “think of the children” political statments are at best trite and more usually an indicator that a “dumb as a stump politico” thinks “they are smarter than you” so can “rabble rouse” with utter tripe at rallies of the “party faithfull”.

Sadly US Politics being the insult that it generally is, I fully expect to see this nonsense start to happen in earnest next year. Unless some in the US have the good sense to lock a lot of such politicians up (unless winter respiratory disease gets them first, which lets be honest would be less costly all round).

twilight z0ne August 22, 2023 8:43 PM

@C U Anon,

zat u @Clive?
Koz, I could swear I detected a whiff of @Clive in that rant, LOL.

Dong-gee August 22, 2023 8:51 PM

I disagree with Mr. Everyone on one point. Healthcare should be provided by the state, and costs cut through routine screenings and preventive measures. Otherwise I agree entirely.

lurker August 23, 2023 12:18 AM

@Clive Robinson
“The US managed to force GPS chips into most phones that go world wide.”

And most of those phones have a means which claims to turn that chip OFF. If there’s a law in the US against turning it off then that’s their problem.

Yes, it’s only a software switch, and yes, it could be bypassed by the spooks. But when an app nags me that it knows I turned GPS off, then we have the possibility,

1) it is off, and the app would like me to please turn it on; or

2) it is on and the app is just nagging so I don’t get suspicious and find out it is using a supposedly off gps.

I think the 2nd option would require me to increase the dose of my medication.

lurker August 23, 2023 12:37 AM


In US v. David Zayas, the Defendant gave sufficient cause for the traffic stop. But the judgement observes that effectively Westchester County traffic cops were running sidekick for the Feds on interstate drug traffic; and that they had “specific articulable facts”, ie. the Defendant was a “person of interest.” At this turn of events I would think the the question of ALPR is moot.

Rousseau August 23, 2023 12:46 AM


3) It’s off, but irrelevant because wifi positioning is more accurate. The app is just hungry for more data.

Clive Robinson August 23, 2023 8:02 AM

@ lurker,

Re : SoCs are tight.

“And most of those phones have a means which claims to turn that chip OFF.”

Err most phones can not turn the GPS “off” because these days all the radio functions are done on a single piece of silicon as a “System on a Chip”(Soc).

Thus the software may if it can, put part but not all of the GPS into “low power mode”, but mostly they won’t. The reason starting GPS “Cold” can be a very slow process especially in minimum cost systems and users don’t like to be told to wait. So the software keeps running the GPS in the background.

Thus that “GPS OFF” option is most likely just a discretionary flag in the OS…

lurker August 23, 2023 1:30 PM

@Clive Robinson
“starting GPS “Cold” can be a very slow process”

Do you mean the boot process for the chip is slow?

Or as I suspect you mean, the process of acquiring data and triangulating from enough satelites for an accurate fix is slow, yes.

I have a couple of GPS apps that I have normally OFF. When I switch ON GPS, then the app, they sometimes show something out of cache, then realise it’s stale, and start acquiring new data. It can take up to 30 seconds to settle. Anyone who thinks 30 seconds is slow should be asked how long it would take with a sextant and almanac, assuming a clear sky and horizon.

lurker August 23, 2023 1:34 PM


My wifi is “off” too. My Scottish ancestors tell me I get better battery life that way.

Gert-Jan August 28, 2023 6:57 AM

So let me get this straight. Can actors like the Russian government simply buy the availability and movement of all motor vehicles in the surveiled area, up to 2 years back (or more likely, since the start of their collection, as they have no insentive to ever delete any collected data)?

And let me guess, if that company ever gets “their” data compromised, they will get a slap on the wrist, say they are sorry, and continue doing what they’re doing?

Why would any government ever allow a private company to gather massive amounts of privacy sensitive information without any restrictions or safeguards?

With its GDPR legislation, the EU would never allow this.

David August 28, 2023 10:02 AM

Applying AI to License Plate Surveillance… Why bother reading and understanding the original post. Let’s just let AI pick some (maybe) relevant reply comments – Mmmkay?

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