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Innovative Uses of Automated License Plate Readers To Enhance Criminal Investigations

NCJ Number
Date Published
June 2019
5 pages
After explaining the capabilities of Automated License Plate Readers (ALPRs), this paper discusses how they can be used to produce leads, facilitate crime scene analysis, identify suspects, and facilitate interrogation.
Each license plate scan from an ALPR camera captures an infrared image of the license plate number, a color image of the vehicle, and its GPS coordinates. The camera then places a date and time stamp on the image. In order to maximize their potential to capture data, some cities have strategically placed ALPR cameras to cover the primary entrance and exit points of the city. ALPRs have the capability to instantaneously cross- reference data captured by an ALPR to license plate numbers entered into state law enforcement databases as stolen, related to a missing person, or as part of a felony crime investigation. In some instances, investigators and crime analysts have used ALPR data to identify the driving patterns of a suspect vehicle; for example, when investigators obtained the license plate number of a vehicle that had been associated with a number of armed robberies, they then determined that the vehicle was registered to an adult female, although the robberies were being committed by three males. Regarding ALPR's use in facilitating interrogation of a suspect, the interviewer can access data from the ALPR system regarding where a suspect's vehicle was located on various dates. Such knowledge can be used to test the suspect's truthfulness.

Date Published: June 1, 2019