Using GIS to interpret automated speed enforcement guidelines and guide deployment decisions in mobile photo enforcement programs

Automated speed enforcement (ASE) guidelines are designed to guide enforcement agencies in operating ASE programs that are effective in improving traffic safety. Given that appropriate deployment decisions are essential to a program's effectiveness, a number of deployment priorities are generally included in most ASE guidelines. However, when implementing the guidelines, most descriptions of deployment goals are so qualitative that they might have multiple quantitative interpretations, and thus affecting the identification of specific deployment considerations. In addition, limited research has been done to improve the process by which guidelines are implemented. Therefore, this paper proposes quantitative measures for an ASE program, in order to facilitate interpretation of the main ASE principles and improve deployment decisions. To illustrate the various types of high-priority deployment considerations, a case study in the city of Edmonton in the province of Alberta, Canada is presented. It explores the deployment outcomes of the mobile photo enforcement (MPE) program in Edmonton, in relation to six priorities identified in the provincial enforcement guidelines. Two performance measures, spatial coverage and enforcement intensity, are assessed for priority sites and non-priority sites. Moreover, the distance halo effects of MPE are considered in the review of spatial coverage. All findings are visualized using Geographic Information Systems, such that high priority sites and coverage of these sites in the historical deployment can be visually assessed. A better understanding of the governing ASE guidelines and how to implement them can help enforcement agencies to improve decision-making and resource allocation, thereby increasing program effectiveness and efficiency.