Forensic genetic genealogy: A profile of cases solved

Abstract

This research undertakes a systematic review of cases cleared using forensic genetic genealogy (FGG) and has produced a dataset and annotated bibliography that can be used for further research. Data was collected to better understand the impact of FGG on a number of metrics relating to substantive, procedural, and distributive justice. FGG has been used primarily to clear cases involving serial and sexual violence against female and vulnerable victims, and in cases involving stranger victimization – cases that have traditionally been more difficult to clear. About 80% of victims were targeted for sexual violence, and about 28% belonged to social groups that are particularly vulnerable to criminal and sexual exploitation. About 79% of suspects and 48% of victims were of European ancestry, although the ancestry of many victims was unknown as they are victims of sexual assault. In the U.S., FGG investigations were primarily conducted in lower-income U.S. counties and were overrepresented in rural areas while being underused in the 50 largest metropolitan areas. The ten largest police departments in the U.S. cleared only 2% of cases and identified 5 suspects. The average time for FGG to clear a case was found to be 12.1 months. The rights of defendants to a fair trial are best secured when cases are cleared quickly and brought to trial in a timely fashion. Many of these cases had been open for many years: this allowed offenders to victimize others, while also leading to higher incidences of wrongful convictions, prosecutions, and innocent suspects being investigated by police. Rates of prior wrongful conviction in the dataset ranged from 2.8% of all crimes, to 3.7% of all homicides. Rates of wrongful prosecutions ranged from 10.1% of all crimes, to 16.5% of all rape-murders. Two persons have been exonerated as a result of an FGG investigation. FGG is advancing the aims of justice in several important ways and should be made more widely available, especially for victims who have been less well-served by the criminal justice system. Further steps to regulate FGG will be welcome in order to further these benefits while reassuring the public of the safety and security of their information.