Citation

Gallidabino M, Weyermann C, Romolo FS, Taroni F. Sci. Justice 2013; 53(1): 41-48.

Copyright

(Copyright © 2013, Forensic Science Society, Publisher Elsevier Publishing)

DOI

10.1016/j.scijus.2011.12.004

PMID

unavailable

Abstract

Estimating the time since discharge of a spent cartridge or a firearm can be useful in criminal situations involving firearms. The analysis of volatile gunshot residue remaining after shooting using solid-phase micro-extraction (SPME) followed by gas chromatography (GC) was proposed to meet this objective. However, current interpretative models suffer from several conceptual drawbacks which render them inadequate to assess the evidential value of a given measurement. This paper aims to fill this gap by proposing a logical approach based on the assessment of likelihood ratios. A probabilistic model was thus developed and applied to a hypothetical scenario where alternative hypotheses about the discharge time of a spent cartridge found on a crime scene were forwarded. In order to estimate the parameters required to implement this solution, a non-linear regression model was proposed and applied to real published data. The proposed approach proved to be a valuable method for interpreting aging-related data. (C) 2011 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

Language: en