科学证据可采性规则研究

科学证据是运用科学知识和科学方法对证据分析所得的判断意见。因此,科学证据属于意见性证言。为防止不可靠的科学证据对法庭的误导,英美法系国家建立了科学证据可采性规则,包括相关性规则、必要性规则、专家证人资格规则、排除规则、可靠性规则。美国科学证据可靠性规则经历了从Frye规则、Daubert规则到修订后的《联邦证据规则》702条的嬗变。我国对鉴定意见的审查主要限于相关性和合法性的审查。由于缺少对鉴定意见可靠性审查的指导与限制,导致了错误裁决的风险。本文提出确立鉴定意见科学可靠性规则的构想,以利于法官排除错误的鉴定意见,同时有助于法庭科学实验室的管理与制度完善,促使法庭科学实验室更严谨更科学地为法庭提供优质的法庭科学服务。     

How do latent print examiners perceive proficiency testing? An analysis of examiner perceptions,performance, and print quality

Proficiency testing has the potential to serve several important purposes for crime laboratories and forensic science disciplines. Scholars and other stakeholders, however, have criticized standard proficiency testing procedures since their implementation in laboratories across the United States. Specifically, many experts label current proficiency tests as non-representative of actual casework, at least in part because they are not sufficiently challenging (e.g., [1], [2], [3], [4]. In the current study, we surveyed latent print examiners (n = 322) after they completed a Collaborative Testing Services proficiency test about their perceptions of test items. We also evaluated respondents’ test performance and used a quality metric algorithm (LQMetrics) to obtain objective indicators of print quality on the test. Results were generally consistent with experts’ concerns about proficiency testing. The low observed error rate, examiner perceptions of relative ease, and high objective print quality metrics together suggest that latent print proficiency testing is not especially challenging. Further, examiners indicated that the test items that most closely resembled real-world casework were also the most difficult and contained prints of the lowest quality. Study findings suggest that including prints of lower quality may increase both the difficulty and representativeness of proficiency testing in latent print examination.     

Weakening forensic science in Spain: from expert evidence to documentary evidence

An amendment in 2002 to the Spanish Code of Criminal Procedure converted into documentary evidence the expert reports prepared by official laboratories aimed at determining the nature, weight, and purity of seized drugs. In most cases, experts are spared from appearance before the courts. This is likely to be extended to other forensic fields. After an overview of criminalistic identification in current forensic science, the objectivity and reliability concepts used by jurists and scientists are considered by comparing the paradigm of individualization with that of likelihood. Subsequently, a detailed critical study is made on the above-mentioned Spanish legal reform, and a comparison is made with the decision on the Melendez-Diaz v. Massachusetts case as ruled by the Supreme Court of the United States. Although the reform is in compliance with the Spanish Constitution, it is at odds with science, in particular regarding the logic underpinning the scientific evaluation of evidence.     

Survey of gunshot residue analysis in forensic science laboratories

The purpose of this survey was to determine the methods of analysis being used on gunshot residue (GSR) samples in forensic science laboratories across the United States. In addition, the two general techniques of GSR analysis are compared and contrasted. Problems encountered by analysts using scanning electron microscopy/energy-dispersive X-ray analysis (SEM/EDX) are discussed.     

《加强美国法庭科学之路》的反响和启示

美国科学院国家研究顾问委员会2009年2月发布的《加强美国法庭科学之路》明确指出目前美国法庭科学领域的很多学科存在严重缺陷,不能很好地为司法审判服务。本文通过对该报告出台背景和一年多来的争论和反响进行分析,对其披露的问题和提出的建议进行了详细解读。目前其主要争议存在于设立独立的国家法庭科学研究院和隔离法庭科学机构与执法...     

物证鉴定的技术方法确认和标准操作规程

物证鉴定中使用的技术方法直接影响和决定了物证检验结果的质量,因此对技术方法的管理是物证鉴定实验室质量保证体系的核心因素之一。开展技术方法的开发确认和内部确认并建立方法的标准操作规程,是保证实验室能够正确选择和使用科学可靠的技术方法,并获得一致结果的主要手段。运行高水平质量保证体系的物证鉴定实验室,应该在案件物证检验工作中使用经过实验室内部确认的技术方法,而且重要新技术方法还应在开发确认基础上进行内部确认,根据方法确认结果建立该方法的标准操作规程。     

Microscopical discrimination of human head hairs sharing a mitochondrial haplogroup

In forensic analyses, determining the level of consensus among examiners for hair comparison conclusions and ancestry identifications is important for assessing the scientific validity of microscopical hair examinations. Here, we present data from an interlaboratory study on the accuracy of microscopical hair comparisons among a subset of experienced hair examiners currently analyzing hair in forensic laboratories across the United States. We examined how well microscopical analysis of hair can reliably be used to differentiate hair samples, many of which were macroscopically similar. Using cut hair samples, many sharing similar macroscopic and microscopic features, collected from individuals who share the same mitochondrial haplogroup as an indication of genetic relatedness, we tested multiple aspects that could impact hair comparisons. This research tested the extent to which morphological features related to ancestry and hair length influence conclusions. Microscopical hair examinations yielded accurate assessments of inclusion/exclusion relative to the reference samples among 85% of the pairwise comparisons. We found shorter hairs had reduced levels of accuracy and hairs from populations examiners were not familiar with may have impacted their ability to resolve features. The reliability of ancestry determinations is not yet clear, but we found indications that the existing categories are only somewhat related to current ethnic and genetic variation. Our results provide support for the continued utility of microscopical comparison of hairs within forensic laboratories and to advocate for a combined analytical approach using both microscopical analysis and mtDNA data on all forensic analyses of hair.     

Forensic Facial Comparison: Issues of Admissibility in the Development of Novel Analytical Technique

Much contemporary debate in forensic science concerns validity and admissibility of scientific evidence in court. In this paper, three current approaches to facial identification—image superimposition, photogrammetry, and morphological analysis—are considered with regard to criteria for scientific evidence in the United States, and England, and Wales. The aim of the paper is to assess the extent to which facial image comparison meets criteria of admissibility in these jurisdictions. The method used is a comparative evaluation of the methods of facial image comparison and their underlying premises against the range of admissibility criteria reported in court rulings and relevant judicial and scientific inquiries in the United States and the United Kingdom. While the techniques of facial image comparison are generally accepted within their practitioner communities, they are not tested, and their error rates are unknown. On that basis, the methods of facial image comparison would appear not to meet the anticipated standards. They are, nevertheless, admitted in court in the United States, and England, and Wales. This paper concludes that further research in science and law will be necessary to more definitively establish admissibility of facial image comparison evidence, as it will for other nascent and novel methods that are potentially influential in court proceedings.     

A Pilot Study Comparing Postmortem and Antemortem CT for the Identification of Unknowns: Could a Forensic Pathologist Do It?

Forensic pathologists are commonly tasked with identifying human remains. Although DNA analysis remains the gold standard in identification, time and cost make it particularly prohibitive. Radiological examination, more specifically analog imaging, is more cost-effective and has been widely used in the medical examiner setting as a means of identification. In the United States, CT imaging is a fairly new imaging modality in the forensic setting, but in more recent years, offices are acquiring CT scans or collaborating with local hospitals to utilize the technology. To broaden the spectrum of potential identifying characteristics, we collected 20 cases with antemortem and postmortem CT images. The results were qualitatively assessed by a forensic pathologist and a nonmedically trained intern, and all cases were correctly identified. This study demonstrates that identification of human remains using visual comparison could be performed with ease by a forensic pathologist with limited CT experience.     

Illuminating the benefits and limitations of forensic light sources

Forensic light sources, such as a Crime-lite, are used in forensic laboratories and by police staff in the examination for, and detection of, biological material. Whilst the benefits of using forensic light sources are relatively well understood, their limitations are less-so. This report details the outcome of studies, validation and review by three forensic laboratories, as well as three case examples, to highlight both the strengths and weaknesses of the tested forensic light sources and to demonstrate that, whilst a useful preliminary screening tool, they should not be used in isolation without subsequent presumptive chemical testing. False positives and negatives are common, and the background substrate and specific biological material present can have a significant effect on the outcome of examination when using a forensic light source.     

中美法庭科学实验室比较研究

本文以中美权威部门发布的统计报告以及有关文献报道的数据为基础,通过比较研究,从实验室分布、规模、人力资源、工作量、专业设置、技术标准化、资金、管理体系和信息化9个方面进行深入分析,找出双方的差异和距离,为我国法庭科学实验室的发展建设提供参考依据。     

The forensic or medicolegal autopsy. Friend or foe?

The major issue in questioning the performance of general pathologists doing medicolegal or forensic autopsies is that they are very often without a firm basis for performing this task. With minimal training in medical school and minimal exposure during their residency, practicing general pathologists, although expected or even forced to do these cases, may face criticism after their performance in a case. The necessity for teaching forensic medicine and pathology in medical schools is obvious, and the necessity of there being more forensic pathology exposure in residency training programs in the United States and overseas is also obvious. Medical educators are responsible for all phases of medicine being taught to medical undergraduates and graduates and must be pressured to support the practice of all kinds of medicine in American communities, including legal or forensic medicine, in those cases in which questions arise that lead to the performance of postmortem examination.     

The current status of forensic science laboratory accreditation in Europe

Forensic science is gaining some solid ground in the area of effective crime prevention, especially in the areas where more sophisticated use of available technology is prevalent. All it takes is high-level cooperation among nations that can help them deal with criminality that adopts a cross-border nature more and more. It is apparent that cooperation will not be enough on its own and this development will require a network of qualified forensic laboratories spread over Europe. It is argued in this paper that forensic science laboratories play an important role in the fight against crime. Another, complimentary argument is that forensic science laboratories need to be better involved in the fight against crime. For this to be achieved, a good level of cooperation should be established and maintained. It is also noted that harmonization is required for such cooperation and seeking accreditation according to an internationally acceptable standard, such as ISO/IEC 17025, will eventually bring harmonization as an end result. Because, ISO/IEC 17025 as an international standard, has been a tool that helps forensic science laboratories in the current trend towards accreditation that can be observed not only in Europe, but also in the rest of the world of forensic science. In the introduction part, ISO/IEC 17025 states that "the acceptance of testing and calibration results between countries should be facilitated if laboratories comply with this international standard and if they obtain accreditation from bodies which have entered into mutual recognition agreements with equivalent bodies in other countries using this international standard." Furthermore, it is emphasized that the use of this international standard will assist in the harmonization of standards and procedures. The background of forensic science cooperation in Europe will be explained by using an existing European forensic science network, i.e. ENFSI, in order to understand the current status of forensic science in Europe better. The Council of Europe and the European Union approaches to forensic science will also be discussed by looking at the legal instruments and documents published by these two European organizations. Data collected from 52 European forensic science laboratories will be examined and findings will be evaluated from a quality assurance and accreditation point of view. The need for harmonization and accreditation in forensic science will be emphasized. The steps that should be taken at the European level for increasing and strengthening the role of European forensic science laboratories in the fight against crime will be given as recommendations in the conclusion.     

The importance of scientific evaluation of biological evidence — Data from eight years of case review

In 2009, the National Research Council published a report stating that the addition of more science and technology into the field of forensic science in the United States would be of great benefit to the judicial system. As a starting point to address this NRC report, one needs to make an assessment of the system. One factor that is continuously requested is an estimate of an error rate. In any given scientific area of forensics that is difficult to quantitate except by external review and audits. After eight years of requested defense review of cases with biological and DNA evidence, most cases appear to be scientifically sound in test methods and procedures. However, there were some cases where errors in the forensic science process did occur. This article takes information compiled from those eight years of defense review and summarizes the cases where errors have been discovered and discusses the scientific implications of these errors. The scope of this article is limited to crime scene collection and forensic science laboratory testing of biological materials for body fluid identification and DNA individualization to a source. The greatest value of defense review comes from (a) providing effective balance and independent oversight to the judicial process and (b) collecting data into a format that can be useful as a guide in training programs.     

A step towards improving workflow practices for volume crime investigations: outcomes of a 90-day trial in South Australia

The provision of forensic science services in volume crime investigations works most successfully as a partnership between police agencies and external forensic laboratories as opposed to a client/provider model where unlimited demand ignores finite resources. The principles of Lean Six Sigma have been applied in various laboratories to improve workflow through identification of wasteful work practices. These strategies are aimed at process optimisation through the application of triaging, a concept that has rarely been studied yet referenced strongly in the literature. The South Australia End to End 90-Day Trial: facilitating quicker justice through timely evidence processing, is a collaborative approach between South Australia Police and Forensic Science South Australia. This trial applied evidence-based policing principles, a law enforcement philosophy that uses research undertaken with scientific processes to inform law-enforcement decision-making. The results demonstrate how a review of processes and the removal of non-value adding activities can improve service delivery while not exhausting those ‘finite resources’.     

法证科学领域的决策

随着法证DNA证据以及它所适用的概率模型日益凸显,反映了传统法证科学的局限性,并使人们对法证科学领域的决策产生了越来越多的质疑,焦点集中在对结论的解读方式和实际运用。分析表明,科学证据的本质不是绝对性或确定性的,而是概率性的;同时,事实审判者需要基于这些概率性的证据对事实作出明确的决定。因此,对于法证科学领域的决策,应当是专家在一系列归纳得出的特定假设基础上,就研究结果的概率进行恰当的报告,由事实审判者承担对概率作出决断的任务。     

物证鉴定的能力验证

能力验证是物证鉴定质量保障体系的重要组成部分,可以非常有效的评估、监控和提高实验室物证鉴定能力和质量。本文论述了物证鉴定能力验证的主要方法、形式、类型和特点,以及在物证鉴定实验室质量管理中的具体应用,介绍了国外物证鉴定实验室参加能力验证活动的历史和现状,并提出在我国物证鉴定实验室广泛开展能力验证活动的思考。     

The New Trial by Ordeal: Rape Kits,Police Practices,and the Unintended Effects of Policy Innovation

One of the most highly touted improvements in the criminal justice response to rape has been the wide‐scale adoption of sexual assault nurse examiner (SANE) programs that provide specialized medical care and forensic evidence collection to victims. Though previous studies have emphasized the benefits of SANE programs in improving criminal case outcomes, this study illustrates how the post‐rape forensic examination can also discourage reporting, investigation, and prosecution. Interviews with local rape care advocates across the United States show how the increasing emphasis on forensic evidence collected through rape kits may provide an opportunity to reflect and enact persistent law enforcement stereotypes toward sexual assault complainants. Unless police resistance to taking rape seriously is confronted and addressed, even well‐intentioned policy reforms such as SANE programs may end up undermining—rather than enhancing—fair and thorough investigation of sexual assault allegations.     

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.