Pre-set estimation-based in-silico silhouette-based methodology for improving the robustness to viewing direction difference for assisting forensic gait analysis

Forensic gait analysis is used to visually and quantitatively analyze information regarding the appearance and style of walking that can be presented as evidence in the court. The demand for analyzing CCTV pedestrian footage in video surveillance has been increasing. The dependence of the accuracy of semiautomatic silhouette-based analysis, often used in forensic science, on the differences in the viewing directions is a very challenging issue that is yet to be resolved for real case applications. Currently, the different viewing directions used in comparison footage significantly decrease the accuracy of same person analysis when using the silhouette-based method, often used in the Japanese forensic science domain. A calibration-based method was previously prosed to resolve this problem, but it requires performing an elaborate measurement procedure at the camera installation site for an accurate analysis. In this study, we propose a novel in-silico silhouette-based analysis method that significantly expands the number of viewing direction pre-set settings to 900 from the 24 used in the previous method. Several software tools have been developed to ensure that all the procedures can be executed on a computer. The experimental results confirm that the accuracy of the proposed method is comparable to that of the calibration-based method. Furthermore, the practical comparison results from actual consultation confirmed the effectiveness of the proposed method under existing viewing direction differences. We therefore anticipate that the proposed method will be beneficial for improving the analysis accuracy in real cases and therefore serve as a substitute of the previous method.     

Gait analysis in forensic medicine*

Recordings from video surveillance systems are used as evidence from crime scenes. It would be useful to perform comparisons between disguised perpetrators and suspects based on their gait. We applied functional anatomical and biomechanical knowledge to analyze the gait of perpetrators, as recorded on surveillance video. Using a structured checklist, which addresses the single body segments during gait, we were able to give a statement concerning the gait patterns. Characteristic parameters were, e.g., varus instability in the knee at heel strike, and larger lateral flexion of the spinal column to one side than the other. Based on these characteristic features, we are able to state with reasonable certainty whether the suspect could be the perpetrator, but it is not possible to identify the perpetrator positively. Nevertheless, we have been involved in several cases where the court has found that this type of gait analysis was a valuable tool.     

Variability and Similarity of Gait as Evaluated by Joint Angles: Implications for Forensic Gait Analysis

Closed‐circuit television (CCTV) footage is used in criminal investigations to compare perpetrators with suspects. Usually, incomplete gait cycles are collected, making evidential gait analysis challenging. This study aimed to analyze the discriminatory power of joint angles throughout a gait cycle. Six sets from 12 men were collected. For each man, a variability range VR (mean ± 1SD) of a specific joint angle at a specific time point (a gait cycle was 100 time points) was calculated. In turn, each individual was compared with the 11 others, and whenever 1 of these 11 had a value within this individual's VR, it counted as positive. By adding the positives throughout the gait cycle, we created simple bar graphs; tall bars indicated a small discriminatory power, short bars indicated a larger one. The highest discriminatory power was at time points 60–80 in the gait cycle. We show how our data can assess gait data from an actual case.     

Issues in the global applications of methodology in forensic anthropology

The project and research reported in this collection of articles follows a long-term historical pattern in forensic anthropology in which new case work and applications reveal methodological issues that need to be addressed. Forensic anthropological analysis in the area of the former Yugoslavia led to questions raised regarding the applicability of methods developed from samples in other regions. The subsequently organized project reveals that such differences exist and new methodology and data are presented to facilitate applications in the Balkan area. The effort illustrates how case applications and court testimony can stimulate research advances. The articles also serve as a model for the improvement of methodology available for global applications.     

Frequencies of morphological characteristics in two contemporary forensic collections: implications for identification

Positive identification relies on comparison of antemortem and postmortem data. Some identifications are based on morphological features such as fracture, pathological condition, and surgical hardware, despite little literature indicating the frequencies of such traits. This study examines whether such features are sufficiently rare as to be deemed individualizing. Data were collected on two modern North American skeletal collections (N=482 individuals). Presence/absence of features was scored by skeletal element and side. Results indicate that frequencies vary by geographic region (higher frequency of fractures and pathological conditions in New Mexico while individuals in Tennessee were more likely to have surgical interventions), many features such as fractures are remarkably common and that even suites of traits may not be individualizing. Caution is warranted when using written data rather than radiographic comparisons as the primary source of identification. The implications of these findings to missing person databases are also discussed.     

Antemortem dental records: attitudes and practices of forensic dentists

This study was designed to provide insight concerning the attitudes and practices of forensic dentists regarding antemortem dental records reviewed for purposes of dental identification. Forensic dentists were invited to participate in a 10 item survey. The majority of the respondents reported a considerable amount of experience in dental identifications of the deceased. Sixty-six percent reported having suspected dental negligence or fraud in their antemortem record reviews. Only 17% believe that a forensic dentist should report suspected dental negligence, while 31% agree that dental fraud should be reported. Their response to additional issues addressed in the study suggests diversity in the practices and attitudes of forensic dentists in the use of antemortem dental records. In conclusion, opening a dialogue among practicing forensic dentists may lead to a standardized set of recommendations by the appropriate societies in the forensic dental community.     

毒物代谢动力学研究在法庭科学中的应用

随着法庭科学的发展以及近年来涉及毒品、毒物等中毒案件的增加,许多研究者对毒物代谢动力学进行研究,并取得了一定的成果.本文综述毒物代谢动力学研究及其在法庭科学中的应用状况,概要介绍毒物代谢动力学的研究现状、研究方法及研究成果,以期为相关研究及实践提供参考和借鉴.     

An Exploration of Sample Representativeness in Anthropometric Facial Comparison*

Abstract: Faces are assumed to be unique, but their use in court has remained problematic as no method of comparison with known error rates has been accepted by the scientific community. Rather than relying on the assumed uniqueness of facial features, previous research has been directed at estimations of face shape frequency. Here, the influence of age, sex, and ancestry on variation was investigated. Statistical shape analysis was used to examine the necessity for sub‐divisions in forensic comparisons, using a large sample of facial images on which 30 anthropometric landmark points had been placed in 3D. Results showed a clear pattern of separation of the sexes in all age groups, and in different age groups in men. It was concluded that sub‐division of databases by sex will be necessary in forensic comparisons. Sub‐division by age may be necessary in men (although not necessarily in women), and may be necessary by ancestry.     

The forensic deaths caused by pesticide poisoning between the years 2006 and 2009 in Izmir, Turkey

Pesticide poisoning is still a significant health problem in Turkey. We conducted a retrospective study of autopsy cases at Izmir Branch of the Council of Forensic Medicine to describe the characteristics of deaths caused by pesticide poisoning between 2006 and 2009. The distributions of the cases according to gender and age were as follows: men 74.1% (n = 40, mean [±SD] age, 44.7 ± 14.1), women 25.9% (n = 14, mean [±SD] age, 39.2 ± 18.9). The majority of pesticide-poisoning deaths were suicides (n = 43, 80%) followed by accidents (n = 4, 8%) and homicide (n = 1, 2%). The manner of death could not be determined in six cases (11%). Suicides mostly occurred at home (n = 26, 63%) (p < 0.05). Methomyl was the most frequent pesticide (n = 9, 17%) among the all cases. This study reported that most of the pesticides found in poisoning cases were highly hazardous types. Combined efforts of medical professionals and law makers are needed for enacting strict laws against highly hazardous pesticides.     

Drunk Person Screening using Eye Thermal Signatures

Temperature distribution on the eyes of drunk persons is studied by means of thermal infrared images. The sclera and the iris are of the same temperature for the sober person, while for the intoxicated person, the sclera temperature increases. Consequently, only the thermal images from the drunk persons are necessary for intoxication screening. Forty‐one participants drank in a controlled alcohol consumption procedure. Their breath alcohol concentration was above the threshold of 0.2 mg/L of exhaled air, which corresponds to about 0.5 mg of alcohol per cubic centimeter of blood. Histogram modification algorithms were employed to prove that for 36 among the 41 intoxicated persons, the sclera becomes hotter. The Student t‐test verified with over 99% confidence the drunk discrimination capabilities of the procedure. The forensic science potential contribution of the method is that face infrared imagery is available to the authorities for supporting intoxication in case of criminal actions.     

植物SSR标记的研究现状及其在法庭科学中的应用

随着SSR分子标记技术的深入研究,其在植物遗传多样性分析、种属鉴定、个体识别中得到越来越广泛的应用。本文就植物SSR分子标记技术的特性、发展、研究现状进行综述,并探讨其在法庭科学中的应用前景,旨在为法庭科学和相关学科中的应用和相关领域中的研究提供参考。     

影像医学在法医学中的应用

个体识别在法庭科学调查中一直是重要的工作,它包括:性别、身高、年龄的推断等。在法庭科学领域中利用影像医学技术进行个体识别,在准确性、实用性方面有特别的意义。本文目的旨在通过广泛系统地回顾国内外法庭科学中的影像学应用,了解现有医学影像技术在法庭科学应用中的优点和不足之处,为进一步完善医学影像学在法庭科学中的应用提供参考。     

The use of orthopedic surgical devices for forensic identification

Surgically implanted devices have become increasingly common in modern skeletal material. Therefore, having the knowledge of the variety of implanted orthopedic devices, their manufacturer, and where to find and how to use identifying numbers in such implants can assist in the identification process when traditional methods are not applicable. Orthopedic device manufacturers are required by the Safe Medical Devices Act of 1990 and the FDA Modernization Act of 1997 to track permanently implanted devices. Manufacturer information on orthopedic devices associates the orthopedic surgeon who implanted the device with the patient. By providing a current list of the most common orthopedic device manufacturers in the U.S.A. and the associated contact information, investigators will have updated tools for the individuation process. Despite numerous complicating factors regarding how device data are tracked, the information presented here can assist forensic professionals with obtaining presumptive and/or positive identifications.     

刑事影像技术新体系

目的阐述刑事影像领域内影像技术及应用的现状和发展。方法从理论方面研究国内外刑事影像技术文献。结果提出了刑事影像影像技术新的框架体系。结论刑事影像技术三个主要组成部分是影像成像检验、影像分析检验和影像合成演示。     

法医骨组织学研究

在实际检案中 ,当现场发现的骨骼残片体积较小时 ,用解剖学观察无法进行骨骼残片的法医鉴定 ,需使用骨组织学的方法进行骨骼残片的个体识别。目前 ,这是法医人类学中一门较活跃的领域 ,即法医骨组织学。法医骨组织学的内容主要包括两个方面 :(1)骨骼残片是否属于人类骨骼 ,或属于何种动物骨骼。这方面的研究包括人类骨骼的组织学特征研究及不同动物的组织学特征研究。 (2 )人类骨骼个体识别的组织学研究。这方面的研究主要包括 ,人类骨骼的组织学特征的年龄判断 ,例如股骨、胫骨、肱骨、锁骨等 ,以及使用骨组织学方法 ,进行人类骨骼的年龄评价的准确性研究。本文对上述内容进行了综述。     

Applicability of DNA analysis on adhesive tape in forensic casework

Adhesive tape is commonly used in crimes and is often the subject of forensic evaluation. DNA analysis of adhesive tape can provide DNA profiles of suspects. The object of this study was to evaluate the applicability of DNA analysis on adhesive tape samples in forensic casework. We retrospectively reviewed all cases involving adhesive tape or similar items received by our institute for DNA analysis during the past 11 years. From 100 forensic cases reviewed, 150 adhesive tape samples were examined. A total of 98 DNA profiles were obtained from these samples. Sixty-two of the profiles provided feasible case-relevant information. In conclusion, DNA profiling of adhesive tape samples can be useful in a variety of forensic cases.     

Virtual autopsy and forensic identification-practical application: a report of one case

The body of an unidentified elderly woman was found trapped in a floodgate. Prior to autopsy, full-body multislice computed tomography (MSCT) was performed for study of bone lesions and cause of death. Age was estimated by analysis of the sternal end of the fourth rib and of the pubic symphyseal medial articular surfaces. The results were then compared with the autopsy findings. MSCT was superior to autopsy in diagnosis of traumatic bone lesions and also revealed dental anomalies and signs of drowning. Age estimation gave a similar result for both methods. This case report illustrates the potential value of MSCT for medico-legal investigations of death: diagnosis of injuries, possibility of determining the cause of death, and anthropological study in order to estimate age or to visualize features likely to enable identification of a corpse.     

Estimation and evidence in forensic anthropology: age-at-death

A great deal has previously been written about the use of skeletal morphological changes in estimating ages-at-death. This article looks in particular at the pubic symphysis, as it was historically one of the first regions to be described in the literature on age estimation. Despite the lengthy history, the value of the pubic symphysis in estimating ages and in providing evidence for putative identifications remains unclear. This lack of clarity primarily stems from the fact that rather ad hoc statistical methods have been applied in previous studies. This article presents a statistical analysis of a large data set (n = 1766) of pubic symphyseal scores from multiple contexts, including anatomical collections, war dead, and victims of genocide. The emphasis is in finding statistical methods that will have the correct "coverage."Coverage" means that if a method has a stated coverage of 50%, then approximately 50% of the individuals in a particular pubic symphyseal stage should have ages that are between the stated age limits, and that approximately 25% should be below the bottom age limit and 25% above the top age limit. In a number of applications it is shown that if an appropriate prior age-at-death distribution is used, then "transition analysis" will provide accurate "coverages," while percentile methods, range methods, and means (+/-standard deviations) will not. Even in cases where there are significant differences in the mean ages-to-transition between populations, the effects on the stated age limits for particular "coverages" are minimal. As a consequence, more emphasis needs to be placed on collecting data on age changes in large samples, rather than focusing on the possibility of inter-population variation in rates of aging.     

Failure of anthropometry as a facial identification technique using high-quality photographs

Anthropometry can be used in certain circumstances to facilitate comparison of a photograph of a suspect with that of the potential offender from surveillance footage. Experimental research was conducted to determine whether anthropometry has a place in forensic practice in confirming the identity of a suspect from a surveillance video. We examined an existing database of photographic lineups, where one video image was compared against 10 photographs, which has previously been used in psychological research. Target (1) and test (10) photos were of high quality, although taken with a different camera. The anthropometric landmarks of right and left ectocanthions, nasion, and stomion were chosen, and proportions and angle values between these landmarks were measured to compare target with test photos. Results indicate that these measurements failed to accurately identify targets. There was also no indication that any of the landmarks made a better comparison than another. It was concluded that, for these landmarks, this method does not generate the consistent results necessary for use as evidence in a court of law.