The false promise of firearms examination validation studies: Lay controls, simplistic comparisons, and the failure to soundly measure misidentification rates

Journal of Forensic Sciences, Journal Year: 2024, Volume and Issue: 69(4), P. 1334 - 1349

Published: April 29, 2024

Abstract Several studies have recently attempted to estimate practitioner accuracy when comparing fired ammunition. But whether this research has included sufficiently challenging comparisons dependent upon expertise for accurate conclusions regarding source remains largely unexplored in the literature. Control groups of lay people comprise one means vetting question, assessing comparison samples were at least enough distinguish between experts and novices. This article therefore utilizes such a group, specifically 82 attorneys, as post hoc control juxtaposes their performance on set cartridge case images from commonly cited study (Duez et al. J Forensic Sci. 2018;63:1069–1084) with that original participant pool professionals. Despite lacking kind formalized training experience common latter, our participants displayed an ability, generally, cases by same versus different guns 327 they performed. And while rates lagged substantially behind those professionals same‐source comparisons, different‐source was essentially indistinguishable trained examiners. indicates although we vetted may provide useful information about professional performing it little offer terms measuring examiners' ability guns. If similar issues pervade other studies, then there is reason rely false‐positive generated.

Language: Английский

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A call for open science in forensics

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(24)

Published: May 23, 2024

The modern canon of open science consists five “schools thought” that justify unfettered access to the fruits scientific research: i) public engagement, ii) democratic right access, iii) efficiency knowledge gain, iv) shared technology, and v) better assessment impact. Here, we introduce a sixth school: due process. Due process under law includes “discovery” by defendant potentially exculpatory evidence held prosecution. When such is scientific, becomes Constitutional mandate for science. To illustrate significance this new school, present case study from forensics, which centers on federally funded investigation reports summary statistics indicating identification decisions made forensic firearms examiners are highly accurate. Because growing concern about validity methods, larger community called release complete analyzable dataset independent audit verification. Those in possession data opposed three years while were used prosecutors gain admissibility criminal trials. paint an incomplete picture hint at flaws experimental design analysis. Under circumstances, withholding underlying proceeding violates Following successful open-science model drug testing through “clinical trials,” place strict requirements timing release, argue registered “forensic trials” ensure transparency accountability.

Language: Английский

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Evaluation of GLOCK 9 mm Firing Pin Aperture Shear Mark Individuality Based on 3,156 Different Pistols (Manufactured Over a 30 Year Period in Two Countries) Using Additional Pattern Matching and IBIS Pattern Recognition

Arab Journal of Forensic Sciences and Forensic Medicine, Journal Year: 2024, Volume and Issue: 6(Special Issue), P. 104 - 116

Published: July 22, 2024

Over a period of 30 years, number fired GLOCK cartridge cases have been evaluated. A total 3156 firearms were used to generate sample the same size. Our research hypothesis was that no from different 9 mm semiautomatic pistols would be mistaken as coming gun (a false match). Using optical comparison microscopy, two separate experiments carried out test this hypothesis. subsample 617 test-fired subjected algorithmic by Integrated Ballistics Identification System (IBIS). The second experiment full set 3,156 manual comparisons using traditional pattern matching. None “matched” either these experiments. empirical findings, an established conservative Bayesian probability model estimate chance case, GLOCK, could firearm when in fact it did not (i.e., match probability).

Language: Английский

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More unjustified inferences from limited data in

Law Probability and Risk, Journal Year: 2024, Volume and Issue: 23(1)

Published: Jan. 1, 2024

Abstract In recent years, multiple scholars have criticized the design of studies exploring accuracy firearms examination methods. Rosenblum et al. extend those criticisms to work Guyll on practitioner performance when comparing fired cartridge cases. But while thoroughly dissect issues regarding equiprobability bias and positive predictive values in study, they do not delve as deeply into other areas such variability participant performance, well sampling participants test samples, that further undercut ability generalize al.’s results. This commentary extends what began explores how low rates error reported by likely underestimate potential for misidentifications casework. Ultimately, given convenience authors should gone beyond descriptive statistics instead draw conclusive inferences classify “a highly valid forensic technique.”

Language: Английский

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