Forensic Sciences Research最新文献

As a leading cause of fatality, motor vehicle collisions comprise a significant proportion of medico-legal cases worldwide. During death investigations into such events, forensic practitioners may be asked to make inferences about the relationship between traumatic injuries and the circumstances of the collision. These interpretations require a thorough understanding of the hard and soft tissue blunt force trauma that results from vehicle collisions. This scoping literature review aimed to assess what is currently known about skeletal fracture patterns in occupants of fatal motor vehicle collisions and how contextual variables influence those fractures. Upon screening the search results from several databases based on a set of pre-defined inclusion criteria, 133 articles were identified including case reports, case series and large empirical studies. Most studies investigated car occupants, followed by motorcyclists, with very few focusing on heavy vehicle occupants. Fractures patterns observed comprised a high prevalence of rib, lower limb, and skull fractures in motorcyclists and a high frequency of skull, vertebral and rib fractures in car occupants, whilst pectoral girdle fractures were rare in both occupant types. The level of contextual detail about the collision varied between studies, with most failing to consider the influence of occupant and crash-related variables on resulting fractures. Further, there was a strong focus on soft tissue trauma and a lack of differentiation between fractures in deceased adult vehicle occupants and other groups. The minimal fracture data available in these studies provides limited assistance to forensic practitioners interpreting motor vehicle collision trauma. Additional research on fracture patterns in the context of the variables that influence trauma is recommended.

With various calls in the forensic scientific literature for pattern-matching disciplines to adopt evaluative reporting, which is also known as the likelihood ratio or logical approach, practitioners used to reporting evidence under a more traditional paradigm may have a level of apprehension and face a steep learning curve. There may be doubts about the benefits of evaluative reporting, when it applies and when it does not, what it actually entails, its validity, and how to explain it in court. These questions and more are answered in this comprehensive collection of frequently asked questions on evaluative reporting. While the focus is on providing context for forensic handwriting examiners, many of the questions and answers are general in nature and the concepts can be applied to other disciplines.

Age estimation of adults is a challenging procedure in forensic practice. Inspired by the previous work by Chinese scholars, we established population-specific age estimation models from the osseous and calcified projections (OCPs) of costal cartilages, using three-dimensional volume-rendering technique. A total of 168 clinical CT scans (2 mm slice thickness) were used to develop the sex-specific age prediction models from a sample of Egyptians, comprising 70 females and 98 males, with documented ages between 12 and 85 years. The sample was also used for validating the Chinese model. We reported the differences between the predictive accuracy of the Egyptian (population specific) and Chinese (non-population specific) models. The most accurate age estimation model was stepwise linear regression with standard error of estimates of 10.9 and 11.8 years in males and females, respectively. For the simple linear regression models, the most accurate formula included OCP of the right second costal cartilage in males and OCP of the left third costal cartilage in females with standard error of estimates of 11.2 and 12.2 years, respectively, and mean absolute error (MAE) of 8.8 and 9.6 years, respectively. By comparison, the best accuracy rates produced by the Chinese vs. the Egyptian models in males and females within 5 years were 30.61% and 32.86% vs. 35.71% and 32.86%, respectively, whereas within 10 years, the accuracy rates increased up to 57.14% and 58.57% vs. 72.45% and 64.29%, respectively. Although the accuracy rates from the Chinese models were lower than those obtained from the Egyptian models, the MAE and least error values were comparable in both sexes. Notable accurate age estimation rates in the advanced age group ≥40 years were reached being 81.25% to 97.92% in males and 69.77% to 93.02% in females. OCP of the right first costal cartilage was the most accurate in cross-population application for males and females with MAE values of 10.7 and 11.03 years, respectively, with balanced accuracy rates of age estimation using the 10-year interval and 40-year cutoff.

Key points: Age differences in calcification form and amount in the seven costal cartilages were found.The best model for males include the second costal cartilage.The best model for females include third or fifth costal cartilages.First OCP is the most accurate in cross-population application regardless of sex.The best OCP in one population is not necessarily the best predictor in both samples.

Like other pattern recognition disciplines, forensic handwriting examination relies on various human factors. Expert opinions in the field are based on visual analysis and comparison, and the evaluation of findings is generally conducted without reference to tabulated data. This high level of subjectivity may contribute to bias and error in the examination process. In this paper, we draw on our research and practical experience to discuss error mitigation on several levels, addressing both aspects of quality management and the individual responsibility of examiners. Because a good understanding of the concept of error is needed to communicate appropriately about this subject, definitions of error-related concepts are provided. We consider contextual information management essential to reduce the potential for cognitive bias in casework. To ensure completeness of findings and avoid omission errors, the use of checklists during a forensic handwriting examination is encouraged, and an exemplary checklist incorporating all the examination steps is provided. We consider the use of a logical reasoning approach to evaluate findings an important step towards robustness and transparency in the examiner's report. An independent, blinded peer review of the examination is recommended as a further key step in error mitigation. Regular participation in testing programmes and continuous training and education are essential to maintaining and improving competency at both individual and organizational levels. Finally, developments in the form of tabulated data and the use of algorithms are considered useful ways of increasing objectivity in the field and minimizing human error.

Establishing a positive identification of human remains found in a forensic setting is often accomplished through DNA, fingerprints, or odontology. However, when these primary identifiers cannot be applied, practitioners can rely on combining points of concordance derived from other identification modalities such as antemortem trauma, pathology, or unique skeletal morphologies to build up a case for identification. In order to conduct these comparisons, forensic anthropologists must be well trained and experienced in human skeletal variation and antemortem trauma to properly evaluate a particular skeletal trait and understand its value with respect to personal identification. In addition to macroscopic analysis of skeletal features and standard radiographic images, recent forensic anthropological efforts of establishing personal identity from the skeleton have employed high-quality clinical imaging technologies. This article presents three forensic anthropological cases in which positive identification was established on the basis of multiple antemortem to postmortem comparison modalities that included skeletal variation, antemortem fracture morphologies, trabecular patterns, dental traits, and implanted surgical devices. These cases use a variety of imaging techniques, such as cranial radiographic images, dental radiographs, computed tomography, photography, and 3D surface scans of the skeletal remains, to achieve personal identification.

Key points: The identification of the remains becomes a top priority in forensic investigations.Dental treatment, implanted surgical devices, anatomical variation, and healed skeletal trauma can provide useful features for the antemortem vs. postmortem records comparison.This article discusses three cases in which multiple forms of antemortem and postmortem imaging were used to compare skeletal areas of interest.All cases were carried out by the Mercyhurst University Forensic Anthropology Team.

"I still don't realize that he's dead.... I cried over it. It makes me sad to know that he was buried unaccompanied on his last trip. We were all shocked." This testimony corresponds to a family whose relative was buried in an anonymous grave 6 months after his disappearance was reported to the police. It is estimated that between 1 000 and 3 000 unidentified bodies are buried in anonymous graves in France each year. Most of these decedents have passed through the medico-legal system. However the identification of these bodies, outside the context of mass disasters, remains a complex problem. Several national and international publications have highlighted the prevalent problem of unidentified burials and the consequences for families who do not know the fate of their loved ones, specifically, whether they are alive or deceased. This 6-year retrospective study (2018-2023), covering a total of 2 324 unidentified decedents admitted to the Institute of Medical-Legal Paris (IMLP), aimed to assess the impact of the identification protocol implemented in 2017 on the number of bodies that remain unidentified (n = 164). In addition, this study aimed to establish profiles for individuals who remained unidentified with the objective of identifying the factors that hinder their identification and developing correlated methods to address these issues. The results of this study were compared with other published studies to highlight the global problem and the ongoing need for collaboration between forensic practitioners and relevant authorities.

Key points: Despite great advances in human identification, unidentified decedents remain a global problem.This 6-year overview study covering a total of 2 324 unidentified bodies admitted to the IMLP provided relevant information about the unidentified decedent population and assessed the impact of a protocol established in 2017 on the rate of deceased buried without identity in Paris.The need to establish a national database in France to properly document and disseminate information on missing persons and to centralize the biological profile of unidentified bodies is key, as without antemortem information or a biometric database there can be no matching.

This article presents a series of three complex forensic cases that posed significant challenges for identifying human remains. These include a mass dam disaster, burnt human remains, and extensively decomposed human remains. Positive identification was achieved using a shadow positioning technique with imaging comparisons of medical findings. After establishing the biological profile, medical data were evaluated with digital radiography and computed tomography examinations the human remains. These aimed to replicate the original (intravitam) traits in the same angulation to examine postsurgical characteristics, as well as the anatomical, pathological, and morphological features, which were sufficient to establish a positive scientific identification. Technological advancements tend to reveal additional skeletal details, making medical data comparisons significantly more effective in the context of anthropological identification. These cases demonstrate that the possibility of identification should never be ignored, even in situations with advanced decomposition.

Key points: Conventional identification methods may not always be applicable in forensic anthropology cases.The presented cases include a mass dam disaster, burnt human remains, and extensively decomposed human remains.These three cases involved successful human identification with medical findings comparisons using the shadow position technique.Identification could be established in these cases, despite challenges, such as fire damage, an incomplete body, and extensive decomposition.These cases suggest medical findings should be considered as biological identifiers rather than secondary identifiers.

Massive parallel sequencing (MPS) has rapidly emerged as a promising technique for forensic DNA typing due to its capacity to simultaneously detect numerous genetic markers and samples in a single reaction, allowing the direct acquisition of sequence information. In this current investigation, the FGID forensic four-in-one DNA typing kit was employed on the DNBSEQ-G99RS high-throughput sequencing platform to simultaneously analyse two types of forensic genetic markers-short tandem repeat (STR) and single nucleotide polymorphism (SNP). A total of 306 DNA markers, comprising Amelogenin, 66 autosomal STR (A-STR) loci, 29 X chromosomal STR (X-STR) loci, 75 Y chromosomal STR (Y-STR) loci, and 135 SNP (132 A-SNP and 3 Y-SNP) loci, were genotyped for 100 unrelated individual samples (50 males and 50 females). As a result, sequence-based STR typing identified 940 alleles on A-STRs, 378 alleles on X-STRs, and 519 alleles on Y-STRs. In comparison with length-based alleles, the number of unique alleles based on sequence increased by 58.18%. Additionally, 97 new sequence variations were observed at 29 STR loci, and MPS sequence information was obtained for the first time at 42 STR loci. Furthermore, when utilizing sequence-based data, forensic parameters exhibited a notable increase in combined power of discrimination (CPD) and combined power of exclusion for A-STR, a slight increase in CPD and combined mean exclusion chance for X-STR, and a marginal increase in discrimination capacity for Y-STR. Moreover, information data for 132 A-SNPs were acquired. As anticipated, our findings highlight the advantages of MPS in forensic genetic applications while contributing novel genetic data for Asian populations in forensic practice.

Identification of unidentified remains involves a comparison of ante- and postmortem features using biological identifiers. Anthropological identifiers, referred to by International Criminal Police Organization (INTERPOL) as secondary identifiers, have often been judged less reliable than DNA, fingerprints and dental records (referred to as primary identifiers). However, anthropological identifiers have been proven as discriminatory as the primary sources in many instances, and play a decisive role in positive identification. To guarantee better use of anthropological identifiers, it is not only essential to develop standard protocols and statistical frameworks, but also to test different identification approaches in cases from daily practice. Evidence of skeletal antemortem trauma can be a valuable aid in the identification process, especially if the exact type of traumatic event causing the injury is identified. Here, we present a case in which the combination of anthropological analysis and imaging confirmed an interesting and unique sequence of antemortem traumatic events in incomplete skeletal remains. The remains were assumed to pertain to an individual who went missing several years earlier, and whose medical records revealed a unique history of trauma to the right femur. The individual had sustained a fracture due to a fall from a high height followed, 10 years after the primary trauma, by a gunshot wound to the same bone; both treated by intramedullary nail fixation. While the anthropological analysis matched the biological profile of the missing individual and identified a healed defect to the right femur compatible with a gunshot wound, the radiological examination indicated that the bone underwent three surgical procedures on different occasions. Radiological examination also identified a pre-existing healed fracture adjacent to the gunshot defect. In addition to presenting the identification process in this specific case, this article discusses the difficulties in antemortem trauma interpretation, importance of combining macroscopic and radiological analysis to aid the reconstruction of previous traumatic events and mechanisms of injury from healed fractures that can play important roles in forensic human identification.