Advancements in Automatic License Plate Recognition (ALPR) systems are changing the way police work is done. Until ALPR technology, our only resources were manual computer entry or a radio call to run a plate, both of which can compromise officer safety and lower efficiency. ALPR technology eliminates the need to enter plate information manually into our mobile data computers, so we can redirect our full attention to driving and on-view (OV) patrol work. Instead, the ALPR system does the work for us.
How ALPR Systems Work
Using cameras and database technologies, ALPR systems operate in the background and automatically scan all license plates within view. The most advanced ALPR systems can read thousands of plates per hour—there’s just no comparison to what we can enter manually and the number an automated ALPR system can run.
The system then processes the information using recognition software and runs the plate against connected local, state and national law enforcement databases to determine if vehicles are stolen, if registered owners are wanted, or if their driver’s licenses are suspended. No action is required from the officer until a match is received on a vehicle. These hits are immediately flagged both audibly and visually.
Not all ALPR Systems are Created Equal
Traditional ALPR systems combine hardware and software packages including specially engineered dual-system cameras with full-color and infrared imaging capabilities. These systems rely on this combination in order to obtain clear images of license plates. However, they can only read license plates at a fixed distance of 10 to 15 feet. To function properly, the cameras require mounting on the exterior of the patrol car and at a fixed angle of 45 degrees to the front of the car, restricting the viewing field.
Today’s more advanced ALPR systems are software-only and eliminate the need for special hardware. They work with a wide range of off-the-shelf surveillance cameras and use traditional optical plate recognition along with object recognition, which gives them the ability to distinguish and read license plates from virtually any video source.
I have used both traditional ALPR systems and, most recently, I have been testing a software-only ALPR system from PlateSmart. I’ve been using the software in my patrol car for more than a year and have seen the results of this advanced ALPR technology first-hand.
Adjustable for Every Scenario
Successful image recognition is the most important part of any ALPR system. I couldn’t make adjustments with the old ALPR system. They were permanently mounted in a secure box on the outside of my patrol car. However, with the software-only ALPR system, there is no need to install bulky, conspicuous cameras on the outside of my car.
My cameras are mounted in the windshield with one pointed right and one left, which allows me to sit on the shoulder from a safe distance and automatically run plates, and even capture traffic in the far lane. I’m able to easily fine-tune my cameras for the situation. I can aim and focus my cameras to reduce blind spots and I can zoom in to read plates at any distance.
I can even monitor from the highway access road on U.S. Highway 19, which cuts through the City of Clearwater. Vehicles on this stretch of highway travel at high speeds, but I can sit behind a concrete barrier where it’s safer.
Come Rain or Shine
Using in-car video cameras also enables these advanced ALPR systems to function on bright sunny days and during heavy rain and other harsh weather without affecting the ability to accurately read license plates. When the sun is rising and I’m watching westbound traffic, I can make a simple tweak based on the angle of the sun and get rid of glare so the plates aren’t blown out.
I can make these adjustments on the fly and as frequently as needed. I’ve even tested my current ALPR system during a tropical storm and it still performed at 88 percent accuracy. The cameras are covert and protected from the elements, and the settings are simple to adjust. You don’t have to hunt for them in a program—it’s all right there in your face.
Prioritizing Hits as They Come
On any given day, 75 percent of the hits from the ALPR system are suspended driver’s licenses. Others are primarily non-criminal violations. I have adjusted the settings to provide customized sounds based on the priority of the hit, so I can immediately recognize a stolen vehicle or missing person as opposed to expired tags. When I hear the higher alert, the adrenaline starts pumping and it’s go time.
On one such incident, I was on a grass shoulder monitoring traffic when I heard the high priority alert. The ALPR system let me know that the hit was related to a missing person. I checked FCIC/NCIC to verify the validity of the alert and found that vehicle was associated with a missing endangered persons report from the department south of Clearwater.
I immediately requested backup and conducted a high-risk traffic stop on the vehicle. The driver was verified as being the missing person and was taken into protective custody. Without the ALPR technology that day, I would not have known this car drove by and this individual would not have been found so quickly. The outcome could have been very different.
Keeping Officers Safe
One of the greatest risks officers face on a daily basis is approaching an unknown vehicle during a traffic stop. We have no idea what to expect from the vehicle’s driver or its occupants. However, advanced ALPR technology gives me real-time, actionable intelligence that results in improved safety. I don’t have to be right up on the car in a bad situation. I can zoom from various distances and quickly get the information I need. The systems works for each person the way you want it to, rather than preset and fixed. That’s something that can’t be done with other systems.
Cost Barriers Come Down
The greatest barrier to large, department-wide deployments of ALPR systems has always been budget. These systems don’t come cheap. Traditional hardware and software packages run about $25,000 per car, while the more advanced systems typically cost significantly less ranging from $10,000 to $15,000 per car.
Every department has budget constraints, but the price tag for the software-only system is much easier to swallow. It’s a substantial costs saving and the flexibility, customization and user-friendliness can’t be beat.
Day or night, rain or shine, these systems just work. It’s like having multiple sets of eyes in my car. My traffic activity is a lot higher and, at the same time, I can concentrate on my surroundings, which means I can proactively police my community and better serve our citizens. These advanced ALPR systems are a force multiplier that can help officers stay safe, fight crime, and save lives, and they will have a lasting impact on the way police work is done today and in the future.
Officer Kevin Klein is with the Clearwater, Fla. Police Department. He has been a Patrol Officer since 2004 and a Traffic Homicide Investigator since 2008. He can be reached at firstname.lastname@example.org.
This article is published in Law and Order Magazine.