Forensic Footwear Reliability: Part I - Participant Demographics and Examiner Agreement

• NCJ Number: 255349
• Journal: Journal of Forensic Sciences Dated: September 2020
• Author(s): Jacqueline A. Speir; Nicole Richetelli; Lesley Hammer
• Date Published: September 2020
• Length: 19 pages
• Grant Number(s): 2016-DN-BX-0152
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical); Report (Study/Research); Report (Grant Sponsored); Program/Project Description
• Award: Understanding the Expert Decision Making Process in Forensic Footwear Examinations: Accuracy, Decision Rules, Predictive Value and the Conditional Probability of an Outcome

Annotation

This article, the first of a three part series, presents the findings of a reliability study that assessed the extent of agreement between forensic footwear examiners in the United States.

Abstract

In order to assess the extent of agreement between forensic footwear examiners in the United States, a reliability study was performed by West Virginia University between February 2017 and August 2018. Over the span of 19 months, 70 examiners each performed 12 comparisons and reported a total of 840 conclusions. For each comparison, participants were queried on a number of factors in order to determine the degree to which different types of features were identified, evaluated, and weighted, before arriving at a final decision regarding the strength of the association or disassociation between questioned and test impressions. Preliminary results from this study are divided into a series of three summaries. This manuscript (Part I) describes participant demographics as well as community agreement in both feature identification, annotation, and final reporting. Results indicate considerable variation in feature identification/annotation (as low as 66.5 percent agreement), but higher consistency in the reporting of overall conclusions. For mated pairs, this agreement was 79.7 percent +/- 14.1 percent (median of 85.7 percent and a 90 percent confidence interval between 75.9 percent and 83.2 percent). For non-mated pairs, the equivalent overall agreement was 89.8 percent +/- 6.69 percent (median of 91.4 percent and a 90 percent confidence interval between 87.4 percent and 92.1 percent). These estimates of agreement are further compared with previous published findings, and collectively, the work extends the body of knowledge concerning reliability in forensic footwear comparisons and conclusions.