Officer Steven Moffa
Alexandria, Virginia Police Department

License Plate Readers (LPR) can be a powerful tool for any police department to possess. Officer Steven Moffa, from the Alexandria (Virginia) Police Department, was one of the most successful officers who participated in the GMU experiment in terms of detecting stolen automobiles and tags. We asked Officer Moffa to give advice to other officers on how to deploy LPR effectively.

When LPR technology was given to me, it had been in use on the streets of Alexandria for approximately one year by a handful of officers. During this time, the LPR deployment was unsuccessful. There were very few, if any, valid hits on license plates, and officers around the department generally disliked the idea of having cameras mounted on the trunks of their vehicles. The consensus after speaking with officers trained in the LPR was that they were a waste of the department’s money. Many officers expressed to me that they rarely turned them on, and when they did, they never got any successful recoveries of stolen license plates or vehicles.

In March of 2010, my supervisor approached me to see whether I would be interested in becoming trained in the use of the LPR system to assist George Mason University in an experimental evaluation. I was apprehensive at first, having only heard negative comments about the technology, but I agreed to participate in the study.

I was trained on the system and had an account set up. Within an hour, I was on the street equipped with an LPR. I was told by the trainer to drive some streets, test the system, and let him know if I had any questions. I found the software to be very intuitive, and I had no problems running tags, or entering tags into the system. Within the first 15 minutes of using the system, I recovered an unoccupied stolen vehicle parked on the side of a heavily traveled road. Upon closer inspection, it appeared that the vehicle had been parked in the same position for a few weeks. I had driven past that location multiple times, but it was not until the LPR was in use, that my attention was drawn to the stolen car and the vehicle could be recovered and returned to the owner.

Recovering a stolen vehicle so quickly motivated me. I informed other officers that I had successfully recovered a stolen vehicle using an LPR, and most felt it was “beginner’s luck.”  The technology was so unproven with the Alexandria Police Department at the time that everyone was skeptical that the use of the LPR could be effective.
The GMU study focused on placing LPR units in randomly selected hot spots of auto theft crime for short spurts of time (the Koper Curve Principle). Within one week, I had recovered my second stolen vehicle using the LPR. A week after that, my third vehicle was recovered. My colleagues began to ask questions about how the system operates and many requested to be trained on its use after seeing my success with it. I had countless numbers of officers stop by the scenes of recovered stolen vehicles or recovered stolen license plates and ask to see the screen and get a demonstration of how the readers worked.

I have now recovered many stolen vehicles, license plates, located persons of interest, and aided in criminal investigations all using the LPR. Some tips and advice I would give other officers would be:

  • At the start of my shift, I ensure that the lenses are clear and that the mount is in the proper position on the trunk. I have found that a camera that is slightly out of position often results in misread tags.
  • At the start of every shift, I download the most current data file of stolen and “of interest” automobiles from the Virginia State Police. This file is updated around midnight every night, and contains all of the current VCIC/NCIC information.
  • Each day, car-to-car messages are automatically sent to our computers. It is important to be vigilant about adding local lookouts that were sent for stolen vehicles after midnight, and manually enter them into the “hot list” database on my computer. This ensures that any vehicles that were reported stolen after the State Police database was updated are now included in the database that scanned plates are compared against.
  • I leave the LPR running as I drive throughout the day. The LPR screen can be minimized in the background of a mobile computer unit so that it does not bog down the system but can be constantly operational even when I am on other calls or conducting preventative patrol. This type of crime prevention allows single resources to be used simultaneously for multiple functions, which can create a cost-savings.
  • Due to the way the cameras are angled, officers may have to adjust the manner in which they drive to maximize the number of tags being read. I have found the camera on the right side of the vehicle allows for the tags to be read in close proximity to the police cruiser, while the left camera will not read tags unless there is more distance between the unit and the tag. As I am driving around the parking lots, I keep as much distance on the left side of the vehicle as possible. Occasionally a parking lot is not wide enough to allow me to do this, so I have to go back and scan the missed vehicles with the camera on the right side.
  • During the George Mason University experiment, I was locked into running the LPR system in areas designated by the research staff. Since that time, I have found many other areas where I have been successful in finding multiple stolen vehicles. I make it a point to drive through each area that I have recovered vehicles from at least once a shift. Not only is this providing a visible presence in the community, but the LPR is looking for stolen cars, stolen license plates, and wanted persons at the same time.
  • Support of first line supervisors is a key element in the success of any deployment. One night, my Sergeant and I decided to do a high visibility traffic post in one of Alexandria’s higher crime neighborhoods. The street is a four-lane road with a double yellow line splitting eastbound and westbound traffic. We closed the right lane eastbound, and the right lane westbound, and funneled traffic into one lane each direction. I found that by angling my cruiser slightly outward, in order to maximize the range of the left camera, I was able to get both lanes of traffic while keeping my cruiser parked in a safe location. I turned the volume of the computer up, and kept the cruiser’s windows down. This allowed me to be outside the vehicle looking for equipment violations, while still monitoring every car that came through the traffic post for any LPR hits. This method appeared to be a successful way of using the LPR, and will be used on future stationary traffic posts. I have also used the LPR while running radar. Parking on a median strip or shoulder, I was able to conduct speed enforcement while running all tags of vehicles passing by my police cruiser.
  • When a lookout is given for a wanted person and there is a license plate involved, I enter this information immediately into the LPR system and search for the vehicle in past reads. Occasionally, I will have found that the vehicle in question had been scanned minutes, hours, or days earlier. I am able to relay this information to the investigating officer. This sometimes allows proving or disproving an alibi that a person was not in a certain area, or narrows down a time frame that an event occurred.  After major incidents where suspects are still unknown, running the LPR in these areas records the tag information, a picture of the vehicle, and a GPS location of the vehicles. This effectively takes a snapshot of what vehicles were in the area at the time, and allows the information to be used by Detectives.

Since I began having success in the use of the LPR, multiple other officers have been trained on the system, and 11 LPR units are now in use on the streets of Alexandria. With proper use and training, the LPR will prove to be an effective tool to patrol officers and investigators. Many officers now seem eager to be trained on the system, and realize the nearly endless possible uses for the LPR. It has changed the way I patrol the streets, and I am looking forward to finding new ways to use the system and having more success with its use.

Officer Moffa was the most successful officer in the GMU LPR study. From March to August of 2010, he recovered 18 stolen vehicles, and 3 sets of stolen license plates. The research team applauds his commitment to evidence-based policing and for participating in one of the first multi-jurisdiction randomized controlled experiments in police scanner technology.

*Opinions or points of view expressed on this page represent the author’s and do not necessarily represent the official position or policies of the Alexandria Police Department.