Citation

Hamby JE, Brundage DJ, Petraco NDK, Thorpe JW. J. Forensic Sci. 2019; 64(2): 551-557.

Affiliation

Department of Pure and Applied Chemistry, Forensic Science Division, University of Strathclyde, 16 Richmond Street, Glasgow, Scotland, G1 1XQ, UK.

Copyright

(Copyright © 2019, American Society for Testing and Materials, Publisher John Wiley and Sons)

DOI

10.1111/1556-4029.13916

PMID

30261099

Abstract

This technical note is an update on a continuing study, first designed and initiated by Brundage et al. over twenty years ago , which seeks to test the community of forensic firearms examiners' ability to associate fired bullets with the barrels through which they passed. To date, 697 participants have utilized over 240 test sets consisting of bullets fired through 10 consecutively rifled RUGER P-85 pistol barrels. Here, we report on the results of the ongoing "10-barrel test" up until the point in time of writing this manuscript. To analyze the totality of data thus far collected, a Bayesian approach was selected. Posterior average examiner error rates are assigned assuming only vague prior information. Given the data found over the course of this diverse decades-long study, our most conservative value for average examiner error rate has a posterior mean of 0.053% with a 95% probability interval of [1.1 × 10^-5 %, 0.16%].

© 2018 American Academy of Forensic Sciences.

Language: en

Keywords

IBIS
; Bayesian statistics; Daubert; SciClops®; ballistics imaging instrumentation; consecutively rifled barrels; criteria for identification; error rates; firearms identification; fired bullets; forensic science; scientific research; subclass characteristics