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Commentators have recommended that forensic scientists' reports contain various disclosures to facilitate comprehension. However, little research has explored whether following best practice recommendations for disclosure impacts on receivers' impressions of the evidence. We examined whether forensic science reports that are more compliant with these best practice recommendations reduced overvaluing of the evidence and sensitized legal and community decision-makers to evidence quality. Across three experiments, 240 legal practitioners/trainees and 566 community decision-makers were presented with a fingerprint or footwear report that was either compliant or non-compliant with best practice recommendations. Participants were then asked to make evaluations and decisions based on the report. We found mixed effects of report compliance. Report compliance affected community participant's evaluations of the persuasiveness of the evidence but had limited impact on the judgments of legal practitioners/trainees. When presented with compliant reports, we found that community participants regarded unknown reliability evidence as less reliable and less persuasive than high reliability evidence, suggesting disclosures helped reduce overvaluing of the evidence and create sensitivity to differences in evidence quality. These results suggest compliance with reporting recommendations does affect community impressions, while only minimally influencing legal impressions of forensic science evidence. The costs and/or benefits of this outcome require further examination., Competing Interests: Declaration of Competing Interest Summersby, S and Ballantyne, K.N. are employees of Victoria Police Forensic Services Department. Edmond G, Kemp, R .I, and Martire, K.A declare no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

There is a body of published research that has evaluated the contribution of forensic science to the criminal justice system, but many disciplines of forensic science remain unexplored in this regard. The aim of this study was to examine the contribution that forensic fire examination services provide to criminal investigations and court processes in arson cases. Forensic fire examination services differ in a number of ways to the disciplines covered in previous research on the impact of forensic evidence on justice outcomes. Forensic fire examinations involve a combination of scene examination and laboratory analyses, and the results can provide critical evidence of whether an incident that has occurred is a criminal offence (i.e. whether a fire has occurred as the result of an act of arson). Forensic fire examination is also a discipline that has faced challenges and undergone development in recent decades regarding its scientific basis and the issue of contextual bias. In this study, data were collated for 273 structural fires that were examined by the forensic fire services in Victoria, Australia. In this jurisdiction, scene and laboratory forensic services are delivered within short time frames with a focus on providing impartial scientific and investigative services to assist criminal investigations conducted by police. The current dataset was highly skewed in terms of criminal justice outcomes and was not suitable for conducting the planned statistical analyses. Nonetheless, the pattern of findings obtained suggested that the inclusion of forensic evidence which supported the prosecution of arson may be associated with an increased likelihood of suspects being charged and defendants found guilty. Examination of the decision-making process of the forensic fire examiners has provided insight into the variety of evidence that is considered by forensic experts in reaching the important conclusion about the origin and cause of structural fires., (Crown Copyright © 2021. Published by Elsevier B.V. All rights reserved.)

Forensic scientists endeavour to explain complex scientific principles to legal decision-makers with limited scientific training (e.g., police, lawyers, judges, and jurors). Much of the time this communication is limited to written opinions in expert reports. Notwithstanding considerable scientific research and debate about the best way to communicate forensic science opinions, it is unclear how much of the advice has translated into forensic science practice. In conducting this descriptive study, we examined the reporting practices adopted by forensic scientists across a range of forensic science disciplines. Specifically, we used a quantitative content analysis approach to identify the conclusion types and additional information submitted by forensic scientists in proficiency tests during 2016 ("What would be the wording of the Conclusions in your report?"). Our analysis of 500 randomly selected responses in eight disciplines indicated that the conclusion type which has received the most criticism in recent years (categorical statements) remains the preferred means of expression in a clear majority of responses. We also found that the provision of additional information often considered necessary for rational evaluation of the evidence (e.g., information about reliability and validity) was rarely reported. These results suggest limited engagement with recent recommendations and are concerning given the gravity of the legal decisions that hinge on accurate and transparent forensic science communication., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 The Chartered Society of Forensic Sciences. All rights reserved.)

We do not know how often false positive reports are made in a range of forensic science disciplines. In the absence of this information it is important to understand the naive beliefs held by potential jurors about forensic science evidence reliability. It is these beliefs that will shape evaluations at trial. This descriptive study adds to our knowledge about naive beliefs by: (1) measuring jury-eligible (lay) perceptions of reliability for the largest range of forensic science disciplines to date, over three waves of data collection between 2011 and 2016 (n=674); (2) calibrating reliability ratings with false positive report estimates; and (3) comparing lay reliability estimates with those of an opportunity sample of forensic practitioners (n=53). Overall the data suggest that both jury-eligible participants and practitioners consider forensic evidence highly reliable. When compared to best or plausible estimates of reliability and error in the forensic sciences these views appear to overestimate reliability and underestimate the frequency of false positive errors. This result highlights the importance of collecting and disseminating empirically derived estimates of false positive error rates to ensure that practitioners and potential jurors have a realistic impression of the value of forensic science evidence., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Peer review features prominently in the forensic sciences. Drawing on recent research and studies, this article examines different types of peer review, specifically: editorial peer review; peer review by the scientific community; technical and administrative review; and verification (and replication). The article reviews the different meanings of these quite disparate activities and their utility in relation to enhancing performance and reducing error. It explains how forensic practitioners should approach and use peer review, as well as how it should be described in expert reports and oral testimony. While peer review has considerable potential, and is a key component of modern quality management systems, its actual value in most forensic science settings has yet to be determined. In consequence, forensic practitioners should reflect on why they use specific review procedures and endeavour to make their actual practices and their potential value transparent to consumers; whether investigators, lawyers, jurors or judges. Claims that review increases the validity of a scientific technique or accuracy of opinions within a particular case should be avoided until empirical evidence is available to support such assertions., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Nonrecombining Y-chromosomal microsatellites (Y-STRs) are widely used to infer population histories, discover genealogical relationships, and identify males for criminal justice purposes. Although a key requirement for their application is reliable mutability knowledge, empirical data are only available for a small number of Y-STRs thus far. To rectify this, we analyzed a large number of 186 Y-STR markers in nearly 2000 DNA-confirmed father-son pairs, covering an overall number of 352,999 meiotic transfers. Following confirmation by DNA sequence analysis, the retrieved mutation data were modeled via a Bayesian approach, resulting in mutation rates from 3.78 × 10(-4) (95% credible interval [CI], 1.38 × 10(-5) - 2.02 × 10(-3)) to 7.44 × 10(-2) (95% CI, 6.51 × 10(-2) - 9.09 × 10(-2)) per marker per generation. With the 924 mutations at 120 Y-STR markers, a nonsignificant excess of repeat losses versus gains (1.16:1), as well as a strong and significant excess of single-repeat versus multirepeat changes (25.23:1), was observed. Although the total repeat number influenced Y-STR locus mutability most strongly, repeat complexity, the length in base pairs of the repeated motif, and the father's age also contributed to Y-STR mutability. To exemplify how to practically utilize this knowledge, we analyzed the 13 most mutable Y-STRs in an independent sample set and empirically proved their suitability for distinguishing close and distantly related males. This finding is expected to revolutionize Y-chromosomal applications in forensic biology, from previous male lineage differentiation toward future male individual identification., (2010 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

DNA transfer is of increasing importance in crime scene situations, partly due to analytical techniques detecting profiles in ever declining amounts of DNA. Whereas the focus has previously been DNA transfer of target sources, the effects of background DNA on transfer and detection of DNA after multiple contact situations have been much less investigated. This study measured the transfer and detection rates of a specific DNA source in the presence of background DNA sources. The presence of background DNA influenced the transfer of DNA differently depending on the combination of biological material and surface type. The detection of a profile from the target DNA decreased after multiple contact situations, due to the reduced total and relative quantity of target DNA, and the increasing complexity of the mixture. The results of this study contribute to a greater understanding of the effects of background DNA sources on DNA transfer and detection. [ABSTRACT FROM AUTHOR]