Automated License Plate Recognition (ALPR) Systems: Policy and Operational Guidance for Law Enforcement
Monday, October 15, 2012
Abstract: Law enforcement agencies throughout the nation are increasingly adopting automated license plate recognition (ALPR) technologies to enhance their enforcement and investigative capabilities, expand their collection of relevant data, and expedite the tedious process of manually comparing vehicle license plates with lists of stolen, wanted, and other vehicles of interest. ALPR systems function to automatically capture an image of the vehicle’s license plate, transform that image into alphanumeric characters, compare the plate number acquired to one or more databases of vehicles of interest, and alert the officer when a vehicle of interest has been observed, all within a matter of seconds.
IACP conducted research sponsored by the National Institute of Justice regarding ALPR implementation among law enforcement agencies and has just released the final report from the study. In order to identify emerging implementation practices and provide operational and policy guidance to the field, IACP surveyed a random sample of 444 local, state, and tribal law enforcement agencies in 2009. A total of 305 agencies responded to the initial survey (68.7%) and three-quarters of respondents (235 agencies, 77.0%) indicated that they were not using ALPR, while 70 agencies (23.0%) responded that they were using ALPR. A longer, more detailed survey was sent to the 70 agencies who confirmed they were using ALPR, and 40 agencies (57.1%) responded.
Survey respondents had typically implemented mobile ALPR systems (95%), and were primarily using ALPR for auto theft (69%), vehicle and traffic enforcement (28%), and investigations (25%). Agencies reported increases in stolen vehicle recoveries (68%), arrests (55%), and productivity (50%). Fewer than half (48%) had developed ALPR policies. Over half (53%) updated their ALPR hot lists wirelessly, and nearly half (43%) updated their hot lists once each day. Agencies varied substantially in the data retention practices. A total of 40% of respondents retain ALPR data for six months or less (n=16). Five respondents (13%) indicated they retain ALPR data indefinitely, while two indicated that retention is based on the storage capacity of the equipment installed.
ALPR technology is a significant tool in the arsenal of law enforcement and public safety agencies. Realizing the core business values that ALPR promises, however, can only be achieved through proper planning, implementation, training, deployment, use, and management of the technology and the information it provides. Like all tools and technologies available to law enforcement, ALPR must also be carefully managed. Policies must be developed and strictly enforced to ensure the quality of the data, the security of the system, compliance with applicable laws and regulations, and the privacy of information gathered.
Download a copy of the report or contact David Roberts at roberts@theiacp.org for more information.
Related File:
IACP_ALPR_Policy_Operational_Guidance.pdf