Integrating police-recorded crime data and DNA data to study serial co-offending behaviour

Abstract

When studying offending behaviour, researchers primarily rely on police-recorded crime data, even though such data contain only detected crimes and known offenders. Using DNA data, which also contain information on unknown offenders, enables researchers to link offenders by identifying their presence at shared crime scenes. In this paper we combine police-recorded crime data with DNA data to study serial co-offending behaviour. We focus on the changes the networks of crimes obtained from police-recorded crime data undergo when integrated with data from unknown offenders in the DNA database. We demonstrate that an integrated dataset reveals more and larger networks of crimes with a larger spatiotemporal spread compared with the police-recorded crime data only.