Measuring the Cost-Effectiveness of New Technologies in Policing: The Case of Automatic License Plate Readers (ALPR)

By Cynthia Lum, Christopher S. Koper, Hyunji Lee, Daniel S. Nagin, Lawrence Sherman

Research Question Can research discover the true cost-effectiveness of new technologies in policing, such as automatic license plate readers (ALPR)? Data We review the findings of many impact tests of introducing ALPR readers in predominantly US police agencies. Methods We place the data in the context of the two key police mandates: public safety and public confidence. We then apply the logic of linking findings specific to the new technology with the two broad mandates. Findings The effect of any technology on police outcomes depends heavily on how it is implemented in the larger context of organizational systems and culture. The effect is also conditioned by a broad body of evidence that the key mandates depend on far broader foundations than on any specific technology. Conclusions Evidence-based policing cannot be built from isolated findings, such as marginal changes in outputs or outcomes associated with new technologies. Linking new technologies to joined-up systems of targeting, testing, and tracking is required before we can ask whether the technologies are cost-effective.

Cambridge Journal of Evidence-Based Policing (2025)