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Automated License Plate Recognition: The Newest Threat to Your Privacy When You Travel

Law enforcement agencies around the country and across the state have a powerful new tool to effortlessly identify and track you while you drive, and it is a real threat to your privacy.

Automatic License Plate Recognition systems or "ALPR" consist of cameras that are either mounted on a vehicle or a pole. The cameras capture an image of the license plate of every passing vehicle, including cars travelling in the opposite direction and cars parked along the curb. Software then converts the license plate image into text and the system compares the license plate number against a hot list of stolen cars, outstanding warrants, amber alerts, parking violations, suspicious persons, or anything else (we have heard reports of tow truck operators using these devices to identify repos). The hot list database can either be loaded before each shift, or wireless and real time.

When the ALPR matches a license plate, the system notifies the officer, who can immediately pull over the identified vehicle. Regardless of whether there is a match, the system stores the image, license plate number, date, time, and GPS location of every passing vehicle. The newest systems can process one plate per second, or nearly 30,000 plates for every eight-hour shift. A large law enforcement agency with ALPRs installed on even a small percentage of its vehicles could effortlessly record tens of millions of license plates per year.

ALPRs raise serious concerns to your privacy because of the system's ability to monitor and track the movements of ALL vehicles, including those registered to people who are not suspected of any crime. Without restrictions, law enforcement agencies can and do store the data gathered by the license plate readers forever, allowing them to monitor where you have traveled and when you traveled there over an extended period of time. In fact, a key selling point for ALPR vendors is the system’s ability to track drivers. As explained by the Los Angeles Police Department Chief of Detectives, the “real value” of the ALPR “comes from the long-term investigative uses of being able to track vehicles—where they’ve been and what they’ve been doing.”  In other words, the cops want to data-mine your driving habits.

ALPR technology has been around for several years, but law enforcement use of the devices has exploded in the past couple of years due to technological advances and significant federal grant money made available. At least 18 Washington law enforcement agencies are using the devices, including the Seattle, Kent and Medina police departments, and the Washington State Patrol currently uses ALPRs at the Seattle and Bainbridge Island ferry terminals, to scan every boarding vehicle.

Currently, Maine and New Hampshire are the only states with laws restricting or limiting ALPR and ALPR data usage. The ACLU of Washington is actively investigating ALPR use in Washington state and will be working to protect your privacy. If you have specific information on how your local police department is using this new technology, please let us know, and keep checking back here for the latest news.

License Plate Recognition sounds a lot like big brother

What kind of country did our forefathers live and die for?
I Hope we can restore much of the freedoms that existed in the times our GREAT NATION'S Founders. I hope that privacy can be restored.
By the way is there a privacy policy required about this monitoring? Can unreasonable violations of reasonable restrictions on use be criminalized and also have large civil penalties? Is it reasonable to permit it at all? Its it constitutional? If you don't like the law, work on changing it!! Remember: "One Person can change the world in a small way" That Person could very well be YOU!!!

Please look up the word fascism. "14 things that all fascist governments have in common". We have most of them. It is really frightening!


There is nothing in the constitution that says you have the right to operate a motor viehicle. Furthermore you signed a contract with your state that they can do what they wish in regards to your driving privilage.

In other words quit breaking the law and you have nothing to worry about. Travel by horse and they will not track you.


ACLU is confused about the law

Brian Alseth! Are you stupid or what?

"The idea of cameras monitoring every highway, boulevard, and alley might strike some Americans as Orwellian. But even the American Civil Liberties Union acknowledges that the public has no right to license plate privacy on public streets. After all, cops can enter plate numbers by hand, so why not by camera?

"There's absolutely no bar on collecting plates in public," says Barry Steinhardt, director of the ACLU's technology and liberty program. "There haven't been any legal challenges, because it's not illegal."

Which is it, genius?

Searching without Probable Cause

No matter how they try to disguise the issue, it is a search for criminal conduct without probable cause. The issue still stands that we are entitled to the pursuit of liberty to move about without government intrusions based on lack of probable cause. Probable cause to search someones data via a license plate is in fact an intrusion of ones liberty to be free without government intrusion without the officers cognizable intuition that a crime is being committed. To search a supposed persons identity via a license plate to later find criminality is unconstitutional. An officer's surveillance of the public to find criminal conduct is unconstitutional. The nexus of a crime requirement must be first recognizably observed, then comes whether or not a crime is being committed. Fishing expeditions for criminal activity when there is no reasonable nexus to connect the person to a crime is unconstitutional. [See Schmerber]The Fourth Amendment is based on the premise of innocence before probable cause of a crime committed. There's no specified target for surveillance based on a criminal suspect identified by human intuition of a criminal suspect. An ALPR device targets everybody as a criminal suspect, which is unconstitutional.

Do you really think that law

Do you really think that law enforcement has any desire to come up with schemes searching for license plate locations to attempt to "manufacture" a potential crime where none has even been proven to exist?? Give me a break!

As a representative of several law enforcement and federal agencies, I can promise you that noone is out there searching for your activities without some specific reason as to why.

If there is a crime and you are a suspect, then yes... your location and traffic patterns will be scrutinized for possible connections. This is NO different that what a typical detective would do for any investigation. They gather data and analyze it to determine the most likely scenario. Just because they are able to gather more data now than ever before and it comes from a camera and a computer instead of a witness does not make the act illegal, nor does it violate any rights that you have always enjoyed.

It was mentioned above, but if you don't want your government issued license plate to be tracked or monitored, then don't buy or register a vehicle.

Bottom line... if you haven't committed a crime, then no law enforcement agent is going to waste their time trying figure out where you've been and why.

Law must adapt to technology

One person here argues that this technology shouldn't be regulated because it's no different from a cop writing down license plates and checking them against a database. If that were true there would be no reason to use this technology.

Technology changes things, and the law should follow.

Using infrared technology to "see inside" buildings is more than just cops looking at buildings, because they can't see inside them if they just look at them. Using ALPR is more than just cops writing down license plates and checking them against a database, because no cop can write down and enter every passing plate. It's humanly impossible.

So in the same way that the Supreme Court decided that infrared technology changes the game in Kyllo v. United States (look it up, cops), we should all kindly recognize that ALPR changes the game.

The law needs to catch up. Kudos to the ACLU for being one of the few organizations trying to keep up with the attacks on our liberty posed by accelerating technological developments.

Where to read about storage of collected information?

Where can the public find information about how SPD's license plate scanning system works? I'd like to read more about it.

I'm curious what, if any, protections are in place for the information gathered. Checking every license plate a squad car passes on public roads against a database of license plate numbers of stolen vehicles is quite different than building a database of when and where that squad car scanned every license plate it scanned.

Can the ALPR system detect new license plates?

Can the ALPR "license plate readers" tell if you got new license plates from the dmv to avoid getting caught if you on the hot list?

Invasion of Privacy

It is concerning lately the amount of power that is being given to law enforcement. It seem that security technologies are giving officials more and more power to invade privacy. Feeling like I am being watched by video cameras all the time makes me wonder what our society is coming to. I am a law abiding citizen and feel that I am entitled to feel completely secure, but not at the cost of my privacy.

ALPR - Idiots have no clue what their rights are! SHEEPLE!

The idiots thinking driving is a privilege and the "Constitution doesn't give you the right to drive" are PRIME examples of how absolutely STUPID America has become. The Constitution does not GIVE ANY RIGHTS! YOU ARE BORN WITH YOUR RIGHTS! The Constitution is there to protect your rights FROM THE GOVERNMENT! Additionally, laws are passed to restrict RIGHTS, NOT GRANT THEM!

You idiots don't deserve rights when you say such IGNORANT SH!T!

I think that the automated

I think that the automated license plate recognition device is a good idea. I can understand that some people might worry about invasion of privacy, but really it is no different than a police officer reading your license plate and doing a manual check. I would think that this would be a great way to have more success during Amber Alerts, and other serious cases. There are so many cars, buses, moving vans, trucks, etc... on the road that this seems like the simplest solution to monitor all vehicles effectively.


Wow...I will get the aluminum foil and duct tape. No sound arguments against the practice, no specific (or even general) examples of alleged abuses. EVERYTHING is potentially against the constitution, I suppose. It would be dependent on the breadth of thinking from a conspiracy theorist's mind.

So what all those that are

So what all those that are for the ALPR system are saying is... having rights is a privilege? My, you are an ignorant race, aren't you.

This technology will

This technology will definitely help in bringing the crime level down. Although it is a threat to the privacy but every coin has two sides and we should look towards the better side. And i think this technology will help restoring law.
CCIE Training

No reason to stop them?

How about "none of their goddamn business"?

License plate tracking by public parking lot where stores are

I got a ticket incorrectly for parking over 2 hours in a lot when I was only there about an hour and 10 minutes. I had been there in the morning, however, left, and came back again in the afternoon. The person monitoring the lots said I was there at 8:22 and at 2:24 so they concluded I was there all day. However, I have a receipt showing I was parked downtown at Pacific Place, had an interview at 11AM, went to Subway at 12:49PM and then came back to this lot at 1:10PM. When I called to protest that they did not respond to my letter showing evidence that I was not there for two hours, they responded with all the dates that I had parked in that lot (going back as far as March!) which is collected in their database. They have my name, home address and who knows what else! I feel strongly that my rights have been violated and their data retention is way off base (over 60 days) and that for a public lot, they are stalking me. She wanted to know if I bought things, and as a consumer, just because I park in a lot and go to a store, doesn't mean that I must buy something. I'm amazed at their tactics and want to take them to court for a wrongful ticket. Tracking my movements as a consumer and now making me afraid to go to this parking lot is also stressful. Anyone want to comment on this to me?

ALPR cameras in Redmond WA

Last week I saw a City of Redmond police cruiser with two ALPR cameras mounted on its roof. I tried to find information on how they use collected data, couldn't find anything, so I emailed with my question. I got a response next day from a Lieutenant who provided his phone number and a link to device description:
The device and the software are impressive. I haven't called, I figured I will leave this to journalists and organizations like ACLU to dig deeper.
I agree with most comments: we do need a regulation on use of this technology.

The data that they have

If this is public space and no privacy is to be expected, Why isn't the data public? The system is ripe for misuse.

he data

If it is public and no expectation of privacy allows their data collection, then they should have no problem with allowing public access to the data.

ALPR cameras in Redmond WA

I received more information from Redmond Police Department (
In response to my question on how data collected by ALPR cameras is used:
When the vehicle [police cruiser with ALPR camera] is in service, the license plate information gathered is checked against the current Washington State Patrol list of stolen vehicles. Although the primary use for the information gathered by the camera is related to checking reported stolen vehicles, the database can also be used for other investigational purposes as needed.
In response to my question on whether the data is stored, and for how long:
All the information gathered by the automatic number plate recognition camera is maintained by our department on a secure database. According to our Police IT representative, the information in database program is set purge after one year from the upload date.

ALPR use in NH

I got stopped by the police in Hollis NH and received a summons for operating with a suspended license. The officer told me he was "randomly scanning plates" which is prohibited by NH law RSA 236:130.. I was just driving by and did not commit any crime or driving violation.(Other than being suspended, which I had no idea it was, and had only been for three days at the time I was stopped) This is clearly a case where even though it is prohibited, the police in NH ARE using this technology to monitor all vehicles. I am actually on my way to court this morning to answer this summons.. I will comment back once we have an outcome..Big brother is indeed watching!

WOW.........I think we also

WOW.........I think we also need to go after our employers now to as they monitor our coming and leaving from work with the aid of time clocks! Last time I checked it was not a "right" to operate a vehicle on our great streets, but a priviledge. That being said we also have to register our vehicles with a home address; in some eyes this too is an invasion of privacy. How about we boycott all the private stores we frequent because they also recording equipment. Here's another one for you.....the same cameras used to "track" your cars are used for the good of the people also. It has been reported, at least where I live that these cameras aided in the arrest of a murder suspect! I think if it was my family who lost someone to a crime like that (just one murderer captured is worth it to me) I would be greatful for this technology! Oh yeah, let's just say no to passports also, who needs to know who comes and goes out of our great country? 911

Threat to Your Privacy but,

this technology seems Threat to Your Privacy but if state uses it well it can be really helpful in dealing with many social, criminal problems. Classifieds
Sydney classifieds
Melbourne classifieds
Adelaide classifieds


My research found that a private company who is selling most of their ALPR units use a private database that local agencies use. Vigilant Video. What data mining can be sold and used. As the Law enforcement Officers may have good intentions and use the system as a law enforcement tool the data they collect could be sold to who and for what?

As far as the comment that if you are doing nothing wrong than why worry, just look what happens when citizens watch the watchers, its a different story.


Scary stuff ......we the people need to stand up and stop these privacy will just get worse if nothing is done...the nazis tracked people and it didint work out to good over there

Don't argue constitutionality

Why get bogged down in the constitutionality ALPR?
The majority will reject the intrusion.
Spread the word, and make it illegal to use.

Just vote to make ALPR illegal to use

Why get dragged down to arguing our human rights.
Spread the word and this technology gets shelved.

And, don't forget who's the Boss.


I want to know what I can do

I want to know what I can do to help stop this..

This system is fully

This system is fully upgradable to whatever they want it to be. And IT IS unconstitutional. Would you like our Federal gov. getting a hold of this.
Well there trying to get the internet and the EAS to have total control.
Obama and other dictator types in DC passed the NDAA.
This is very scary stuff.

Inform yourself before you go off calling names. very ignorant!!!

Homeland Security

The War on Drugs is the sole purpose this technology is emplemented. The government knows exactly where wholesale prices and large quanitites of illegal substances are located, they just know they have failed time and again to erradicate the supply, and it is much more difficult to find probable cause to enter private property vs. a motor vehicle. They are tracking movements of vehicles moving from these hot spot locations and they know the distribution patterns. With this technology, vehicles leaving the hotspots are placed in the "suspicious" nationwide database and officers are notified once that vehicle enters into a distribution zone. The vehicle is pulled over for a manufactured reason, most of the time for swerving, a probable cause search is warranted from a drug sniffing dog, and the bust is complete. This is an incredible invasion of privacy and corruption on the police force as a whole. The fact police officers have to make up a reason to pull you over vs. stating you were tracked for suspicious activiy indicates there is recognition of constitutional rights being violated.

What about mistakes by police

Recently, the supreme court has allowed strip searches for minor offenses. The case that started the debate was one of a man who's wife was driving his vehicle and was stopped for speeding. There was a warrant on him for an unpaid ticket, which was in fact paid and he had the proof in the glove box. Didn't matter-he was still jailed, sent through the system until a judge threw out his charge. Now, how many cops are going to scan plates, see hits for outstanding warrants which may in fact be false, stop your car for no obvious traffic violation, and cart you off to jail? Maybe not in larger areas, but where I live, the cops are looking for ways to generate revenue and justify the size of their force.

Towing companies

Towing companies in Ohio are using this.....why is THAT not an invasion of privacy? These are not law enforcement agents who now have your's "Tow Truck Joe", looking to make commision from a tow! Why do they have a right to my information?

Take em down. Simple. Act,

Take em down. Simple. Act, don't whine.

I would like to det a

I would like to det a database of all known police license plates and then run this software like a new style radar detector so i can be alerted to all unmarked police cars.

right to travel

When I signed my drivers license I was never informed that I was giving up a right inorder to have a priviledge. There fore by not disclosing all the facts the contract is null and void, and further more my state ID and license have been expired for some time and on that point my contract is no longer in effect, or in good standing.

Also I do believe that " the state cannot deminish the rights of the people" Herato v California,

The assurtion of federal rights when plainly and reasonably made, is not to be defeated under the name of local practicce. Davis v Wechsler

Where the rights, secured by the constitution are involved, there can be no rule making  or legislation to abrogate them. Miranda v Arizona

yes indeed

I have never seen such a plain, straight forward way of saying just that, the constitutipon is a tool to be used by the people for the people to control their government.


ALPR Issue

Here is my very legitimate issue with it.  They scan the plate, the plate belongs to a car registered to a person with a revoked/suspended license, they pull it over.


TWICE I have been pulled over driving a friend whose license is suspended because they scanned her plate and pulled me over.  I was not speeding, nor breaking any other driving laws, therefore, I'm being harassed and pulled over without cause.

This is a major violation

First thing, I can't believe this got passed. My car was stolen last year and SPD wouldn't even acknowledge the case. Multiple other vehicles in my area (after talking to neighbors) have also been stolen and the police reluctantly respond.

I was pulled over weeks later, mind you SPD never came to talk to me or take any type of statement/evidence, for my car being reported stolen! All i can do now days is wonder what hole this "officers" come from and how they think new technology will assist them in being more affective. 

So now i have to count on being pulled over everytime i get spotted by this "technology" just because the SPD runs itself un effectively? Can't wait for the neighborhood meeting this week to discuss this. I'm sure everyone is looking forward to the random lights flashing behind them making them late to work.

Not sure how this is going to turn out for the city as a whole but hopefully it will not be a burden to the tax payers.

The Real Picture is on them

ahh it's all coming together now, more and more sophisticated technology not only invading our privacy, but taking millions of jobs away and as a result destroying our economy,our trust and our future, thanks to good'ol Bill Gates who got the ball rolling. You see, what it's done so far is use automated telephone assistance instead of people, steered us to use the web  for most public official business,implemented banking institutions with limited personnel and unlimited online service that cut the job force by more than half as most agencies and businesses have adopted and this is just to name a few. Government and other officials, if they're really as smart as they think they are, will not be so eager to advocate and accept these new devices because the future of their jobs and future are at stake too. I see a future of paranoia, desperation, depression, greif, obesity (consuming comfort foods) and prescription drug addicts so say the least. Real physical manpower in jobs not only will turn this country around but will breathe new hope to our next innocent generation. Intelligence without morals was Hitler's stragedy which equals=trajedy.. overall everything has a pro and con, but are you looking at the short range or long range? Sometimes the fight to resist is more powerful than the fight to overcome.

Basic purpose of the

Basic purpose of the Constitution was to LIMIT government, so doing it by hand, limits the potential for government over-reaching.

only lawbreakers need fear government

What laws were the Jews, gays, other "undesireables" breaking in Germany during the reign of German fascism?


who cares if they scan your plate? did you do something wrong? this system catches kidnappers, car thieves, terrorists. its designed to keep us safe and aid the police in doing their job quicker. i don;t care if they know where i am going or where i have been. quit being so damn paranoid.

This is a clear violation of

This is a clear violation of the 4th ammendment.

"this system catches

"this system catches kidnappers, car thieves, terrorists." This system only catches those who fail to pay the state. It is a 'for profit' mechanism and nothing more. For Profit laws directly violate the Rule of Law. It also violates basic Human Rights.

I thought the whole premise was that terrorists hate the west because we have rights. They have no reason to hate us any more.

So silly...

Guess who in the USA has the largest network and database of ALPR cameras? Nope, not the state police, nope not the FBI, no again not the NSA. You were fooled if you thought it was a government agency. The correct answer is the vehicle repossession industry. That's right, its the tow truck repo guys. They are using the same automatic license plate recognition hardware and software in the search for vehicles with overdue financing loans. They have built a national database fed by local tow truck operators. They take the same ALPR pictures with date, time, and GPS location metadata. The data is so valuable that they use unmarked, non-descript, spotter cars in addition to the actual tow trucks to gather the data crusing streets and hotel and apartment parking lots day and night. And their database is for sale to anyone with cash to pay. Divorce lawyers, bail bondsmen and skip tracers, current and future potential employers. And the best part, the data is privately collected and privately managed from start to finish with no government oversight or regulation what so ever. Got cash and a plate number and you too can have all the tracking you want. And what are you really going to do, pass a law prohibiting private persons and businesses from taking photographs and video in public places? Your local police looking for stolen cars, drug dealers, and missing person vehicles are your friend compared to the real "big brother" who is watching which is private industry.


wait until this information is compromised and the information falls into the wrong hands and your life is drastically changed. Maybe you might see things differently.

This is against our rights ,

This is against our rights , It does not matter if we break the law or not you fucking idot! It is none of they're business what we do.

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