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Several organizations have outlined the need for standardized methods for conducting physical fit comparisons. This study answers this call by developing and evaluating a systematic and transparent approach for examining, documenting, and interpreting textile physical fits, using qualitative feature descriptors and a quantitative metric (Edge Similarity Score, ESS) for the physical fit examination of textile materials. Here, the results from 1027 textile physical fit comparisons are reported. This includes the evaluation of inter and intraanalyst variation when using this method for hand‐torn and stabbed fabrics. ESS higher than 80% and ESS lower than 20%, respectively, support fit and nonfit conclusions. The results show that analyst accuracy ranges from 88% to 100% when using this criterion. The estimated false‐positive rate for this dataset (2% false positives, 10 of 477 true nonfit pairs) demonstrates the importance of assessing the quality of a physical fit during an examination and reveals that potential errors are low, but possible in textile physical fit examinations. The risk of error must be accounted for in the interpretation and verification processes. Further analysis shows that factors such as the separation method, construction, and design of the samples do not substantially influence the ESS values. Additionally, the proposed method is independently evaluated by 15 practitioners in an interlaboratory exercise that demonstrates satisfactory reproducibility between participants. The standardized terminology and documentation criteria are the first steps toward validating approaches to streamline the peer review process, minimize bias and subjectivity, and convey the probative value of the evidence. [ABSTRACT FROM AUTHOR]

A physical fit is an important observation that can result from the forensic analysis of trace evidence as it conveys a high degree of association between two items. However, physical fit examinations can be time‐consuming, and potential bias from analysts may affect judgment. To overcome these shortcomings, a data analysis algorithm using mutual information and a decision tree has been developed to support practitioners in interpreting the evidence. We created these tools using data obtained from physical fit examinations of duct tape and textiles analyzed in previous studies, along with the reasoning behind the analysts' decisions. The relative feature importance is described by material type, enhancing the knowledge base in this field. Compared with the human analysis, the algorithms provided accuracies above 90%, with an improved rate of true positives for most duct tape subsets. Conversely, false positives were observed in high‐quality scissor cut (HQ‐HT‐S) duct tape and textiles. As such, it is advised to use these algorithms in tandem with human analysis. Furthermore, the study evaluated the accuracy of physical fits when only partial sample lengths are available. The results of this investigation indicated that acceptable accuracies for correctly identifying true fits and non‐fits occurred when at least 35% of a sample length was present. However, lower accuracies were observed for samples prone to stretching or distortion. Therefore, the models described here can provide a valuable supplementary tool but should not be the sole means of evaluating samples. [ABSTRACT FROM AUTHOR]

Glass is a trace material commonly found at crime scenes that can provide valuable information at early investigative stages and during a trial. The forensic analysis of glass has steadily evolved since the 1970s with numerous technological advances in spectroscopy and spectrometry. This article presents an advanced review of the recent literature concerning the forensic examination of glass evidence and discusses the current state and future opportunities of the discipline. The review focuses on established elemental spectrochemical techniques, including Inductively Coupled Plasma methods (ICP), laser‐ablation, and x‐ray Fluorescence (XRF) methods, and newer applications using Laser Induced Breakdown Spectroscopy (LIBS), Raman Spectroscopy, and accelerator and reactor nuclear techniques. A brief overview of the transfer, persistence, interpretation, and analytical schemes implemented in the field is revised to provide context to the discussion of the capabilities and limitations of the current and emerging technology. This article is categorized under:Forensic Chemistry and Trace Evidence > Trace Evidence [ABSTRACT FROM AUTHOR]