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

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% agreement), but higher consistency in the reporting of overall conclusions. For mated pairs, this agreement was 79.7% ± 14.1% (median of 85.7% and a 90% confidence interval between 75.9% and 83.2%). For nonmated pairs, the equivalent overall agreement was 89.8% ± 6.69% (median of 91.4% and a 90% confidence interval between 87.4% and 92.1%). 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.