Quantifying the Specific Deterrent Effects of DNA Databases

Forensic science has come to play an increasingly important role in aiding criminal investigations. The field has experienced numerous advances over the last decade. This has lead courts, practitioners, prosecutors and legislators to embrace the tools it offers, in general, and DNA profiling, in particular. The National Institute of Justice is consequently soliciting applications to study a broad array of social science research issues that these advances have raised. This proposal describes a project that the Urban Institute will undertake in order to assess and quantify the specific deterrent effects of DNA databases. The research team will acquire administrative records from various criminal justice agencies in the state of Florida and construct appropriate cohorts of individuals who have had their DNA profiles entered into Florida's DNA Investigative Support Database (which is accessible to law enforcement agencies nationwide through the FBI's CODIS system). Detailed dated criminal histories of these individuals will be compiled, studied, and analyzed to construct models of their criminal history accumulation process. These models will be used to make plausible counterfactual claims about their future offending behavior. Comparisons with this group's actual future offending patterns will then yield estimates of the number of crimes prevented by the entry of their DNA profiles into a database. The modeling strategy proposed will allow researchers to disentangle specific deterrent effects from incapacitation effects of imprisonment as well as the specific deterrent (or criminogenic) effects of incarceration. As such, the strategy promises to offer clear insights into the true future benefits to be expected from DNA databases. Since the analytical framework developed in this study could be applied to perform similar computations in other states, or for investigating specific deterrent effects of other interventions, an auxiliary objective of this project is to help the broader researcher and practitioner communities perform similar studies in other jurisdictions. To that end, the team will produce, in addition to a final technical report and a policy brief detailing our findings, a manual that will provide readers sufficient detail to conduct a similar analysis with other data systems.

ca/ncf