Evaluating Gunshot Detection Technology (GDT) to Aid in the Reduction of Firearms Violence

Statement of the Problem: This project will investigate the degree to which gunshot detection technology (GDT) aids in the response, investigation, and prevention of firearms violence and related crime. While the ability of the technology to detect firearm discharges is well established through prior NIJ-funded research, no rigorous research to date has documented the implementation, use, and impact of GDT on desired firearms violence reduction outcomes. Subjects: Milwaukee, WI; Denver, CO; and Richmond, CA. Partnerships: ShotSpotterTM SST, Inc., The Police Foundation, and the referenced cities. Research Design and Methods: The Urban Institute (Urban) will examine the impact of GDT on firearms violence and related crime as measured by reported crime, arrests, calls for service, and response times. Structural break time series and difference-in-differences (DiD) analyses (employing matched comparison areas) will measure if firearms violence and related crimes declined in the areas served by the technology. Qualitative data on GDT deployment and use will complement this empirical inquiry. Research questions are: 1. How are GDT systems employed by law enforcement for crime control and prevention purposes? 2. To what degree does GDT use reduce response time, enhance investigations, increase case clearances, support prosecutions, improve police-community relations, and reduce gun violence? 3. Has GDT use resulted in spatial displacement of crime or diffusion of benefits? 4. What is the cost of GDT deployment, maintenance, training, and use in relation to its benefits in crime reduction? Analysis: Data will be analyzed through: (1) Structural break analyses of response times, case clearance rates, gun-related reported crimes, and calls for service in areas covered by GDT sensors; (2) DiD analyses of changes in gun crimes in GDT coverage areas versus comparison areas matched on historical crime rates, land use, and demographic characteristics; (3) Spatial and weighted displacement quotient analyses of gun-related crime trends in 500- and 1,000-foot buffers surrounding GDT deployment areas; and (4) Qualitative analysis based on interviews with law enforcement and community stakeholders to inform how GDT is used and provide context with which to interpret findings as well as to explore other impacts, including firearm-related investigations and prosecutions. Cost-benefit analyses will assess whether the benefits in crime reduction associated with GDT outweigh the costs of the technology. Products: Urban will provide a final summary overview, deliver presentations to both researcher and practitioner audiences, and submit journal articles. Data and documentation will be submitted for data archiving after removing identifying information. This project contains a research and/or development component, as defined in applicable law. ca/ncf