Comparison of Methodologies Used in Homicide Investigations to Collect, Prioritize, and Eliminate Persons of Interest: A Case Study of Three Dutch Real-World Homicide Cases

Abstract

This paper provides a comparison between four methodologies that assist criminal investigators in homicide investigations. The Person of Interest Priority Assessment Tool, Trace Investigate and Evaluate, Rasterfahndung, and Analysis of Competing Hypotheses are compared on their performance in the collection, prioritization, and elimination phase of homicide cases in today’s digital era. Three recent Dutch homicide cases are used. The use of categories during collection can assist criminal investigators in the early inclusion of the perpetrator into the investigation, however, in this digital era, the number of persons of interest becomes too large to humanly handle. All four methodologies use techniques to assign weight to pieces of evidence; further research is required to evaluate the effectiveness of these techniques when the amount of pieces of evidence explodes. The use of pre-set elimination categories shows the least promising result leaving most persons of interest not-eliminated by the currently used methodologies.

Getting the Perpetrator Incorporated and Prioritized in Homicide Investigations: The Development and Evaluation of a Case-Specific Element Library (C-SEL)

“…To evaluate the effectiveness of the C-SEL methodology, three real-world and recently-solved Dutch homicide cases were used: the cases described by Sutmuller et al [ 18 ] to compare the four methodologies that were introduced in the background section (POIPAT, TIE, Rasterfahndung, and ACH). To be able to compare the results with the other four methodologies, the same performance criteria for the collection and prioritization phase were used as in Sutmuller et al [ 18 ].…”

“…For the other elements, the number of persons of interest in the complete case file that met these elements was used. The approximations for TIE and Rasterfahndung were taken from Sutmuller et al [18].…”

“…Summary of percentages in which the perpetrator is prioritized by the initial score of the case-specific element library (C-SEL IS) alone and after adjustment of the underlying factors (C-SEL AA) as well as Trace Investigate Evaluate (TIE), Person of Interest Priority Assessment Tool (POIPAT), Rasterfahndung, and Analysis of Competing Hypotheses (ACH). The percentages for TIE, POIPAT, Rasterfahndung, and ACH were taken from Sutmuller et al [18].…”

“…Sutmuller, den Hengst, Barros, and van Gelder [ 18 ] provided a comparison between these four methodologies that are currently being used in homicide investigations. The four methodologies were evaluated across three recently solved Dutch homicide cases using the following questions: can the methodology incorporate the name of the perpetrator into the investigation within the first two weeks (collection) and can the methodology prioritize the perpetrator within the top ten percent of persons of interest (prioritize)?…”

“…The methodologies showed comparable and modest results. All methodologies failed to meet the performance criterion for collection and prioritization in one of the three cases [ 18 ]. In addition, Sutmuller et al [ 18 ] showed that a large number of persons of interest, tens of thousands, would be incorporated using the methodologies and stated that it is important to take into account the reliability and credibility of the source of evidence [ 18 ].…”