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.     

Reliable Gait Recognition Using 3D Reconstructions and Random Forests – An Anthropometric Approach

Photogrammetric measurements of bodily dimensions and analysis of gait patterns in CCTV are important tools in forensic investigations but accurate extraction of the measurements are challenging. This study tested whether manual annotation of the joint centers on 3D reconstructions could provide reliable recognition. Sixteen participants performed normal walking where 3D reconstructions were obtained continually. Segment lengths and kinematics from the extremities were manually extracted by eight expert observers. The results showed that all the participants were recognized, assuming the same expert annotated the data. Recognition based on data annotated by different experts was less reliable achieving 72.6% correct recognitions as some parameters were heavily affected by interobserver variability. This study verified that 3D reconstructions are feasible for forensic gait analysis as an improved alternative to conventional CCTV. However, further studies are needed to account for the use of different clothing, field conditions, etc.     

美国法庭科学证据的应用与发展

＂法庭科学＂萌芽于古代中国,兴盛于近现代西方国家,最终发展成为具备完整科学体系的现代意义上的法庭科学学科。法庭科学证据的应用与发展显然与法庭科学的发展与应用密切相关,它们相互制约,相互促进。美国司法制度中关于法庭科学证据的证明力、可信度、可采性的分立质疑对法庭科学本身的发展无疑起到鞭策与促进作用。美国法庭科学证据的司法制度以及常用的一些传统与高技术法庭科学证据的使用过程中存在的许多问题,理解法庭科学证据标准,对我国法庭科学及其证据的研究与应用有所启迪。     

Public beliefs about the accuracy and importance of forensic evidence in the United States

Recent advances in forensic science, especially the use of DNA technology, have revealed that faulty forensic analyses may have contributed to miscarriages of justice. In this study we build on recent research on the general public’s perceptions of the accuracy of 10 forensic science techniques and of each stage in the investigation process. We find that individuals in the United States hold a pessimistic view of the forensic science investigation process, believing that an error can occur about half of the time at each stage of the process. We find that respondents believe that forensics are far from perfect, with accuracy rates ranging from a low of 55% for voice analysis to a high of 83% for DNA analysis, with most techniques being considered between 65% and 75% accurate. Nevertheless, respondents still believe that forensic evidence is a key part of a criminal case, with nearly 30% of respondents believing that the absence of forensic evidence is sufficient for a prosecutor to drop the case and nearly 40% believing that the presence of forensic evidence – even if other forms of evidence suggest that the defendant is not guilty – is enough to convict the defendant.     

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.     

道路交通事故法医检验技术的研究进展

近年来,经济快速发展和机动车数量急剧增多,道路交通事故频发和伤亡人数不断上升已经成为备受关注的全球性问题。法医检验作为交通事故处理中重要的证据,其鉴定意见直接影响着当事方的权益和事故处理。不容置疑,法医检验技术的运用对鉴定意见有十分重要的影响作用。本文对国内外法医检验技术的最新研究进展和应用进行综述,供同行实践工作中参考。     

论实物证据的鉴真与鉴定——以美国法为参照的分析

鉴真是指确定实物证据真品性的证明活动,“两个证据”规定为鉴真提供了明确的法律渊源.实物证据不存在真实性推定、事实和二级事实的区分以及证据可采信的预备问题是鉴真的三大理论基础.鉴真和鉴定都是确定证据真实性的方法,鉴真是鉴定的前提和基础,鉴定是鉴真的必要延伸和补充,它们与最佳证据规则相结合,最大限度地保障了证据的真品性和真实性.我国应构造诉讼化的鉴真程序.     

论专家辅助人意见——以刑事辩护为视角的分析

我国2012年新《刑事诉讼法》首次设立专家辅助人制度，对鉴定意见的质证提供了技术上的支持，对于刑事辩护来说意义重大。从证据法的角度看来，专家辅助人意见具有言词证据、意见证据、弹劾证据的多重属性，因此意见的内容应围绕鉴定意见中的专门性问题，并结合《刑事诉讼法》及相关司法解释对鉴定意见的审查判断规则来提出；而法庭对于鉴定意见的审查也应从准入资格与可靠性两方面进行，以免专家辅助人意见替代鉴定意见来主导审判。     

Assessing Cognitive Bias in Forensic Decisions: A Review and Outlook

In recent years, a number of studies have demonstrated that forensic examiners can be biased by task-irrelevant contextual information. However, concerns relating to methodological flaws and ecological validity attenuate how much the current body of knowledge can be applied to real-life operational settings. The current review takes a narrative approach to synthesizing the literature across forensic science. Further, the review considers three main issues: (i) primary research on contextual bias within forensic science; (ii) methodological criticisms of this research; (iii) an alternative perspective that task-irrelevant contextual information does not always lead to error. One suggestion for future research is outlined, which is that studies on contextual bias in forensic decisions should be conducted in collaboration between forensic scientists and cognitive psychologists. Only then can rigorous and ecological valid experiments be created that will be able to assess how task-irrelevant contextual information influences forensic analysis and judgments in operationally valid settings.     

植物物证的法医学应用

随着植物物证在案件侦破过程中的作用日益明显,应用植物学研究方法为刑事案件提供线索、证据的"法医植物学"越来越受到关注.法医植物学常用的实验技术有形态学检验、理化检验、分子遗传学检验等.本文通过整理法医植物学研究的相关文献及案例,以列举的形式简要阐述不同检验方法的利弊,总结法医植物学应用中需要注意的问题,供案件现场勘验时...     

司法会计鉴定应当是检察机关司法会计工作重点——暨谈对检察机关司法会计工作发展趋势之认识

随着我国检察机关法律监督职责的加强与完善,检察机关司法会计鉴定人的地位与作用为此也已经或将发生重大变化.我们应将司法会计鉴定作为检察机关司法会计工作的重点,并将咨询和文证审查作为其不可或缺的两翼;同时,坚持充分体现司法鉴定本色和证据规则要求.     

近十年来我国现代法医昆虫学研究进展

法医昆虫学(Forensic entomology)指的是应用昆虫学知识解决法律上问题的法医学分支学科,在死后间隔时间判断,特别是腐败尸体的死后间隔时间判断等方面有著无可比拟的优越性。本文讨论了法医昆虫学的研究领域,从理论研究与实践应用两方面概述了近十年来法医昆虫学在我国的进展。     

On using gait in forensic biometrics

Given the continuing advances in gait biometrics, it appears prudent to investigate the translation of these techniques for forensic use. We address the question as to the confidence that might be given between any two such measurements. We use the locations of ankle, knee, and hip to derive a measure of the match between walking subjects in image sequences. The Instantaneous Posture Match algorithm, using Harr templates, kinematics, and anthropomorphic knowledge is used to determine their location. This is demonstrated using real CCTV recorded at Gatwick International Airport, laboratory images from the multiview CASIA-B data set, and an example of real scene of crime video. To access the measurement confidence, we study the mean intra- and inter-match scores as a function of database size. These measures converge to constant and separate values, indicating that the match measure derived from individual comparisons is considerably smaller than the average match measure from a population.     

Identifying and measuring juror pre-trial bias for forensic evidence: development and validation of the Forensic Evidence Evaluation Bias Scale

Abstract

Previous research has provided support for the impact of juror pre-trial bias on judicial decision making, particularly in cases where the evidence presented at trial is of weak or ambiguous probative value. In an effort to identify whether a pre-trial bias for forensic evidence exists, the Forensic Evidence Evaluation Bias Scale (FEEBS) was developed and tested. The results of a principal components analysis suggested that two distinct constructs were being measured, corresponding to a pro-prosecution and pro-defence bias toward forensic evidence. In a second validation study, scores on these two subscales were compared with other existing juror bias measures (Juror Bias Scale and Belief in a Just World) and in a mock juror decision making task only the pro-prosecution subscale of the FEEBS predicted the perceived strength of forensic evidence. A partial mediation model is presented which explains the relationship between this bias and verdict preferences. The implications of this potential juror bias are discussed in the context of real juries, the CSI Effect (which refers to anecdotal claims that jurors are biased by the popularity of fictional representations of forensic science on television) and peremptory challenges, as well as future research directions.     

A review of the historical use and criticisms of gait analysis evidence

The use of gait analysis is a well-established facet of practice for many professions and a fundamental aspect of clinical practice. In recent times, gait analysis evidence has emerged as a new area of forensic practice. As its use has continued to spread and develop, the area of work has come under close scrutiny and subsequent criticism. The purpose of this paper is to examine the historical use of gait analysis evidence and consider the criticisms of this work. Through the use of the historical records of cases within the public domain it has been determined that gait analysis as evidence was first presented in court over 175?years ago, although it has only been utilized by experts in more recent times. The quality of analysis underpinning such evidence has been variable, and has been undertaken by both non-expert and expert witnesses. The work undertaken by expert witnesses appears to have been both non-scientific and scientific in nature, though there is limited reporting of cases involving scientific approaches. Given the variation in the quality of the methodologies utilized, there is the potential for confusion within the courts, where it may be difficult for the judge or jury to determine the appropriate weight that can be attributed to the evidence. It is concluded that future publications should explore the scientific basis of forensic gait analysis to evaluate standards, reliability and validity, as well as reporting the methodologies utilized in relevant cases in the field. It is also recommended that courts consider in greater depth an expert's theoretical approach and experience prior to admitting their evidence. The publication of ‘Forensic gait analysis: a primer for courts’, although limited in some aspects of its consideration of practice, is a welcome addition to the information available for guidance.     

试论专家在司法鉴定中的角色定位

作为科学、技术或其他专门知识的“载体”,专家在诉讼中的职能越来越广泛.由于诉讼模式的差异,专家在诉讼解决专门性问题时具有不同的角色定位.当事人主义诉讼模式下,专家被视为当事人的证据方法;职权主义诉讼模式下,专家充当法官的辅助人.在两大法系相互借鉴和融合中,专家兼具当事人证据方法和法官辅助人的角色.我国鉴定制度带有浓厚的职权主义色彩,鉴定人在诉讼中扮演着“专门性问题法官”的角色.我国应借鉴德国和日本的做法,将鉴定人定位为法官的辅助人兼当事人的证据方法,从厘清鉴定启动权、鉴定实施权、鉴定意见审查权的性质及相互关系入手,完善我国司法鉴定制度.     

The CSI effect and the Canadian and the Australian Jury

Television shows, such as CBS's CSI and its spin-offs CSI: Miami; CSI: Las Vegas; and CSI: New York, have sparked the imagination of thousands of viewers who want to become forensic scientists. The shows' fictional portrayals of crime scene investigations have prompted fears that jurors will demand DNA and other forensic evidence before they will convict, and have unrealistic expectations of that evidence. This has been dubbed the "CSI effect." This phenomenon was explored using results from a Canadian study based on 605 surveys of Canadian college students who would be considered jury-eligible and Australian quantitative and qualitative findings from a study that surveyed and interviewed real posttrial jurors. Information about the way jurors deal with forensic evidence in the context of other evidence and feedback about the way in which understanding such evidence could be increased were gained from both these studies. The comparison provides insights into the knowledge base of jurors, permitting adaptation of methods of presenting forensic information by lawyers and experts in court, based on evidence rather than folklore. While the Canadian juror data showed statistically significant findings that jurors are clearly influenced in their treatment of some forensic evidence by their television-viewing habits, reassuringly, no support was found in either study for the operation of a detrimental CSI effect as defined above. In the Australian study, in fact, support was found for the proposition that jurors assess forensic evidence in a balanced and thoughtful manner.     

试论我国司法鉴定回避制度的完善

司法鉴定回避制度是确保鉴定公正的重要制度.司法鉴定回避制度应当具备适应现实所需的开放的特性.现行关于鉴定回避的立法条文存在文本性缺陷.需要根据实践情况,在构建公正和高效的指导原则下,规范鉴定回避的情形和程序,以促进鉴定回避制度的完善.     

Evidentiary Standards for Forensic Anthropology*

Abstract: As issues of professional standards and error rates continue to be addressed in the courts, forensic anthropologists should be proactive by developing and adhering to professional standards of best practice. There has been recent increased awareness and interest in critically assessing some of the techniques used by forensic anthropologists, but issues such as validation, error rates, and professional standards have seldom been addressed. Here we explore the legal impetus for this trend and identify areas where we can improve regarding these issues. We also discuss the recent formation of a Scientific Working Group for Forensic Anthropology (SWGANTH), which was created with the purposes of encouraging discourse among anthropologists and developing and disseminating consensus guidelines for the practice of forensic anthropology. We believe it is possible and advisable for anthropologists to seek and espouse research and methodological techniques that meet higher standards to ensure quality and consistency in our field.     

知识产权案件司法鉴定程序之探讨

在知识产权案件的审理中,知识产权司法鉴定扮演着越来越重要的角色,特别是涉及争议知识产权事项的鉴定已成为案件定性的关键性证据。鉴定启动程序应当从司法鉴定特性出发,对鉴定实施中的法律与事实事项作出初步界分,以程序公正来架构＂鉴定人、专家陪审员和专家辅助人＂的审判程式,同时可以附之知识产权技术顾问,以此来维护和保障司法的实体公正。