Evaluating forensic DNA databases

The practice of retaining DNA profiles in databases, either obtained from individuals involved in criminal investigations or retrieved from suspected crime scenes, has spread globally since the creation of the UK’s National DNA Database (NDNAD) in 1995. Yet as States continue to create and expand national forensic DNA databases, the specific goals of such databases remain poorly articulated, with paltry efforts expended in gauging ‘effectiveness’. While the UK NDNAD (the focus of this chapter) may have led directly to convictions in both serious and non-violent crimes, an aggregate impact upon public security goals remains elusive. Further, evidence produced to justify large-scale databasing has relied upon narrow parameters of assessment, focussed upon highly circumscribed outcomes. Yet without clarity of purpose and evidence of impact, States run the risk that such databases will be viewed by citizens as ineffective, and/or illegitimate, ergo lacking integrity and losing public confidence. DNA databases can pursue public security objectives, but in order to do so, must ensure their integrity. Appraisal then of the ‘effectiveness’ of a DNA database needs to be both dissected and expanded to encompass measures of the ‘integrity’ of a database. Such an approach to evaluation should augment anecdotal evidence and elementary statistical analysis, inaugurating a more realistic, and holistic, accounting of DNA databases and their impact.