Testing and validating AnTraGoS algorithms with impact beating spatters

Abstract

The reconstruction of the area of origin of spatter patterns is usually a fundamental step to the determination of the area of the crime scene where the victim was wounded. In this field, for almost a decade, the italian Polizia di Stato has employed AnTraGoS, a forensic software which implements a probabilistic approach to identify the area where the horizontal projections of the trajectories of a set of blood drops converge (area of convergence) and to estimate the height of origin. In this paper we summarize a series of tests performed on a published dataset of spatter patterns, whose results confirm the validity of AnTraGoS and of its algorithms. As a side result, some useful suggestions are derived, concerning the determination of the height of origin, within a statistical and fluid dynamic approach.