Many local, state or federal law enforcement organizations are using or investigating the use of license plate readers (LPRs). Even the acronym, LPR, has become a common part of the law enforcement vernacular. Although the term itself may be self-explanatory, the related search for vendors, discerning applications and subsequent implementation concerns remain a bit more nebulous and confusing.
I'm with the Houston High Intensity Drug Trafficking Area (HIDTA), and we have confronted the issues surrounding the acquisition and deployment of LPRs. I offer the following discourse not as an absolute, how-to manual, but rather an introductory outline that could be titled How to Buy an LPR System for Dummies.
Although there are many commercial and security applications for LPRs, the focus of this article is general law enforcement applications, and it provides key questions you must ask before acquiring an LPR for your department.
Why Do You Want an LPR?
In many cases, the LPR request will come from an auto theft unit because the most obvious application of LPR technology is to locate stolen vehicles. Officers simply place a camera in a squad car that has some kind of access to NCIC data. As it cruises on routine patrol, it will scan the road, identify any stolen cars and alert the attending officer.
If this is all you want your LPR to do, your system can be less robust. But many other applications for LPRs exist.
The type and placement of an LPR system depends on its intended uses. The following are just a few of the applications you may want to consider when choosing the right type of LPR for your department:
Search for stolen vehicles;
Search for vehicles related to Amber/silver alerts, robberies, homicides and other crimes with immediacy;
Track the movements of and/or intercept gang members, drug traffickers and other criminals;
Photograph vehicles and their drivers for investigative use;
Search for vehicles related to outstanding warrants;
Special enforcement operations (e.g., checking for predators' vehicles in school zones);
Search for "shadow" vehicles escorting drug or money couriers; and
Intelligence applications.
For our purposes at the HIDTA, LPRs have two basic applications: interdiction and investigation. An LPR, when used in conjunction with various databases, will alert the operator when it encounters a vehicle-of-interest (VOI), and some sort of immediate enforcement action will ensue. In those instances, the LPR is used to interdict VOIs and serve as an officer safety tool.
The investigative application is more complex and variable. Example: A narcotics investigator could place a VOI into an LPR database and request notification when the vehicle is encountered, but also request no enforcement action. Gang units could place lookouts for suspected gangbangers to observe their movements and request no enforcement action.
The license data LPRs collect can be stored for an indeterminable length of time, limited only by the server containing the information. Some LPRs temporarily store information in the camera housing or in a nearby server, but all will eventually download it into a larger server, either automatically or manually. Investigators from all disciplines can then query that server to learn if a certain VOI was in a particular area at a specified time and, perhaps, who was driving it.
Key Considerations
Before contacting a vendor, you should know what you want and how to ask for it. The following questions will help you get started. In addition, the glossary (see sidebar, p.44) contains terms that will help you knowledgeably converse with a vendor and understand what they're saying.
What kind of LPR do you want to buy?
This is the first issue you must decide. There are four basic types of LPR systems. Some are less noticeable to traffic, but none are strictly covert.
1. Static/stationary (a camera mounted on a structure from which it can view a roadway). Such a system can serve as the foundation for a highway enforcement program, providing data for interdiction and investigative use. It may require a nearby server and Internet access to transmit data.
2. Mobile (a camera mounted on/in a vehicle). Such a system is an excellent tactical tool for urban law enforcement compared to a static format, but may have limited results in highway interdiction. Some are portable and can be moved from car to car using a magnetic mount, and some will update NCIC data via a wireless connection to a central server.
3. Portable checkpoint. This LPR acts like a static unit when in place, but can be easily moved. It's designed for secondary sites for highway interdiction, and features rear-plate only configuration.
4. Handheld. A handheld wireless device looks like a big calculator and is generally used in parking lots. Its functional distance is limited.
It's evident you must determine what you want to accomplish with the LPR before deciding what type to buy. For example, interdicting stolen vehicles along a particular route may be served best by a static camera system. Airport details may want the handheld units. Mobile units deployed in high-crime areas are effective for both interdiction and investigations.
Who do I need for this project?
You'll need to assemble several people to see this acquisition and implementation to fruition. The assembled group must establish and share a vision for the project.
The group should consist of a contracting officer, a tech person, a representative from the unit that will use the LPR, the decision maker and an assigned point-of-contact (POC) for the vendor(s). If your project is multi-agency, you may want to assemble a steering committee or users group. If your project is heavily oriented toward stolen vehicles, you may want to liaise with automobile insurance organizations, which may be able to help with funding and provide some technical expertise.
The POC is the ad hoc project manager who will ensure all the department's entities are fulfilling their obligations in sync with the vendors. Most vendors complain that they have to contact too many people to get projects completed; a POC simplifies and accelerates the process.
Other Considerations
You'll need to know where and how the information will be stored after the LPR collects license numbers. Example: A mobile unit may collect data and store it in the camera or vehicle until after the shift, at which time it's downloaded into a server. Some mobile units can automatically transmit the data to an area server as it collects data, or whenever it gets within range of a wireless network. Some stationary units store the data on a nearby server that has to be periodically transferred to a master server. The point is that you need to consider these factors as you are designing your system and working with the vendor.
Consider the following questions:
Where will the server(s) reside?
How long will the information be stored?
What memory capacity is needed?
How are backups conducted?
What and how many databases will the LPR be connected to?
Who will have access to the data, and by what means?
Define terms with your staff & the vendor.
Just like law enforcement people, technical people have their own vernacular. And, as can be expected sometimes, the same term may have different meanings, connotations and nuances to different people. You must define and clarify terms at the beginning of discussions with your staff.
It's equally important to define terms with your vendor(s). For example, many vendors and technicians will use the word "scalability." What exactly does that mean? The glossary provided here is only a guide to let you know what terms you may encounter and subsequently need to come to consensus on.
Can your LPR system share data with other jurisdictions?
Perhaps the biggest failure with law enforcement's adoption of technology is in the myopic implementation and deployment of databases. The proliferation of "stove-piped" intelligence or "fusion" centers is but one example. The variety of gang databases throughout the nation is another example.
The use of LPR systems integrated into departments will increase exponentially over the next decade, so every department embarking on this venture should look beyond the city, county or federal application and think about integrating or sharing with other systems at some point in time. A key consideration when deciding on a vendor is if their system can share data with other products.
What are the rules?
State departments of transportation may restrict where cameras can be placed and how they can be used. Who will enter and remove lookouts? What types of lookouts will be allowed? If other agencies will participate in your project, you should begin with a multi-agency group to decide these issues.
Physical Security
Stationary LPRs are easily identifiable and subject to vandalism. Consideration should be given to their placement and access. Also evaluate the environmental factors and plan for the worst case scenarios.
Technical Capabilities
Definitions of many of the following characteristics may differ among manufacturers. You must know the terms, define them with the vendor and verify the vendor's claims with live, in-the-field demonstrations and conversations with other departments that use the equipment.
Read rate: How many license plates can the LPR read in one minute (or another defined period of time)? And you must define the LPR's application when assessing read-rate. For example, is the traffic moving fast, or is the mobile unit scanning a neighborhood?
Accuracy rate: This term is not one you're likely to encounter in exactly the same way each time, and may be couched as "capture rate" or some other term. This term asks, "Of the number of vehicles the LPR can read, how many of those license plates are accurately recorded?" You'll find a number of discrepancies among the vendors in how they determine their accuracy. Ask them how they determine this rate and to prove it!
Retro vs. non-retro reflective plates: The glossary explains the difference between these two types of plates. Can the vendor's LPR capture both? Is that important to you?
Plate origin: Can the LPR identify the state or province from which the plate comes? Is that important to you?
What to capture?
Do you want to capture the rear plate only? Do you want both plates? Do you need color? Do you need a picture of the vehicle? Do you want a picture of the driver?
Do you want to capture cars, trucks, trailers, motorcycles, etc.? Some commercial vehicles may have multiple plates. Is it important that you capture them? Can the reader you're considering handle a scenario like a commercial trailer with multiple plates displayed or two motorcycles occupying the same lane of traffic and travelling side by side?
Some technology will photograph the vehicle even when it can't read the plate. Is that important to you?
Is the system expandable? Is the system scalable? Does the system offer real-time performance? As the LPR captures data, is that information sent immediately to a storage database?
Reliability
What do you consider acceptable reliability? Prior to selecting any vendor, request contacts in other departments that use its product and have a detailed conversation with those end users.
Some vendors offer 24/7 technical support. Some guarantee a physical response to a problem within a specified time period. Identify what your needs are to determine if the vendor meets them.
Maintenance
What's the cost for maintenance in contractual dollars (is it built into your purchase contract), employee time, parts and labor? What is acceptable maintenance?
Back Office Software (BOS)
This is certainly a technical capability that will take considerable study, time and assets. For that reason, it's listed as a separate category of concern. Other than the camera system that captures plates, the most important and thought-provoking dialogue you'll have with your staff and the vendor is the back office operation.
Basically the "back office" operation defines what and how you'll deal with the license plate data. You should have many options, and each will probably cost more and require technical attention.
Simply stated, an LPR system captures license plate information and stores it somehow and somewhere. You have to decide what you'll do with that information.
This is a limited list of issues concerning the BOS:
Will the LPR data automatically query a database that will alert the system of a VOI?
The databases will include NCIC and what else?
How much customization can you do to the BOS? Example: Can it send electronic notification of an alert to a Blackberry?
How detailed and customizable is the BOS' reporting capability?
How compatible is it with your existing systems?
Can it be linked to vehicle registration and/or criminal history databases?
How big of a server do you need?
Where will it be housed?
Who will act as the systems administrator?
Who will be the official custodian of records?
How much time will it take to administer the system per week?
What are the protocols for accessing the system (e.g., passwords, application for passwords, etc.)?
The Bottom Line
Eventually, almost every law enforcement agency in the United States will employ some sort of automated LPR system. I hope they do so knowledgeably and with the ultimate thought of sharing their data with other agencies.
I sincerely believe LPRs can change law enforcement capabilities and expectations as much as car radios and walkie-talkies did. At this fledgling state of LPR technology and use, we need a pragmatic, disciplined and planned approach by federal, state and local agencies in unity with one another.
VENDORS
The following is a short list of vendors that sell LPR systems. The list contains companies I'm acquainted with through use, demonstrations or word-of-mouth.
- Appian
- AutoVu
- Bolo Incorporated
- Civica
- Cyclops Technology
- DataWorks Plus
- Elsag North America
- EyeNet Enforcement Systems
- G2Tactics
- Genetec/Autovu
- HiTech
- Inex Technology
- Motorola
- NDI
- Perceptics
- PIPS
- Vigilant Video
GLOSSARY
Accuracy rate: Of the plates read, how many are accurately captured.
ALPR: Automated license plate reader.
Camera: The device that sees the plate and captures it.
Expandable: Additional systems can be added.
Handheld LPR: Physically held in the hand and pointed at license plates.
Infrared: Allows the picture to be taken without a flash. May limit recognition to retro-reflective plates.
LPR: License plate reader.
Mobile checkpoint: Acts like a stationary LPR but is movable.
Mobile LPR: One affixed to a vehicle; can be permanent or movable from vehicle to vehicle.
Non-reflective plate: Does not contain material that reflects light back to the camera.
Read rate: License plates read over a predetermined period of time (e.g., frames/second).
Reflective plate: Contains material that reflects light back to the camera. May become non-reflective when covered in dirt, snow or other substance specifically designed to foil some LPRs.
Scalable: Additional software/cameras can be added to the system with no loss in efficiency.
Stationary LPR: Permanently mounted in a fixed location.
Stan Furce currently serves as Director at the Houston HIDTA. He formerly served as a DEA Special Agent (CA, Belgium, Japan and Texas).