Linking serial homicide – towards an ecologically valid application

Linking serial homicide – towards an ecologically valid application Tom Pakkanen, Jukka Sirén, Angelo Zappalà, Patrick Jern, Dario Bosco, Andrea Berti, Pekka Santtila Journal of Criminological Research, Policy and Practice, Vol. 7, No. 1, pp.18-33 Crime linkage analysis (CLA) can be applied in the police investigation-phase to sift through a database to find behaviorally similar cases to the one under investigation and in the trial-phase to try to prove that the perpetrator of two or more offences is the same, by showing similarity and distinctiveness in the offences. Lately, research has moved toward more naturalistic settings, analyzing data sets that are as similar to actual crime databases as possible. One such step has been to include one-off offences in the data sets, but this has not yet been done with homicide. The purpose of this paper is to investigate how linking accuracy of serial homicide is affected as a function of added hard-to-solve one-off offences. A sample (N = 117–1160) of Italian serial homicides (n = 116) and hard-to-solve one-off homicides (n = 1–1044, simulated from 45 cases) was analyzed using a Bayesian approach to identify series membership, and a case by case comparison of similarity using Jaccard’s coefficient. Linking accuracy was evaluated using receiver operating characteristics and by examining the sensitivity and specificity of the model. After an initial dip in linking accuracy (as measured by...
Source: Journal of Criminological Research, Policy and Practice - Category: Criminology Authors: Source Type: research