对73起重大疑难命案的实证分析——从刑事证据的收集、固定、审查判断和运用的角度

命案中的证据收集瑕疵表现为重嫌疑人有罪供述,轻物证、书证;重有罪证据,轻无罪辩解;勘查现场不及时、不细致;非法取证等。证据固定瑕疵表现为靠重复讯问固定证据;不善于运用录音录像固定证据;物证检验不及时;刑事技术鉴定结论不明。证据审查判断和运用瑕疵表现为轻信鉴定结论等科技证据;忽略物证证明的间接性;依赖口供又不会运用口供;不能正确对待嫌疑人的辩解;不能正确认识证据数量和证明力的关系;不善于排除证据矛盾。造成这些瑕疪的原因在于不能准确把握"命案必破"的内涵;办案思维方法不正确;不会把握证据确实、充分的定罪标准等。建议强化责任意识;增强人权意识;强化证据意识;正确运用有罪口供;建立切实可行的非法证据排除制度;制订科学合理的考核办法。     

物证鉴定在刑事诉讼中的作用

随着我国法律与法制的进一步健全,物证鉴定得到了越来越多人的认同,物证鉴定的结论在刑事诉讼中起到越来越大的作用。其中关于物证鉴定与刑事诉讼之间所存在的内在关系和法理联系已经引起学术界和司法实务部门的广泛关注和研讨。本文从诉讼证据出发,引出物证鉴定的重要意义,希望能为相关的法理研究提供一个新的理论视角。证据与物证证据是指能证明某一事物客观存在或某一主张成立的有关事实材料犤1犦。根据我国诉讼法的规定,证据有以下几种:物证、书证;证人证言;被害人陈述;犯罪嫌疑人和被告人的供述和辩解;鉴定结论;勘验检查笔录;视听资料…     

刑事鉴定结论审查运用问题研究

近年来,鉴定结论这种证据形式在刑事诉讼领域中得到了越来越广泛的应用,同时也出现一些新情况新问题.其中,如何规范鉴定检材的来源和提取程序,能否将运用科技手段推理得出的鉴定结论用作直接证据等问题,都已成为人们关注的热点.深人研究这些问题,有助于更好地运用鉴定结论证据,从而最大限度地减少和避免错案的发生.     

物证鉴定技术违规对鉴定结论证明力的影响及对策

物证鉴定技术是自然科学在法律中的应用,它采用科学方法对涉案的各类物证进行分析后得出确定性结论。鉴定结论作为一种诉讼证据,对现代型诉讼发挥了重要作用和影响。但也带来了许多诉讼上的问题。本文列举了目前物证鉴定工作中出现的较为普遍的技术违规并就这些违规对鉴定结论证明力所造成的影响进行了初步分析,并提出应尽快制定鉴定法、鉴定技术标准和技术质量检测评估体系,以规范物证鉴定工作,确保其科学性、可靠性。     

试析物证技术鉴定结论的评断

作为司法鉴定结论的一种，物证技术鉴定结论是对于实物证据的专门问题的鉴定结果。是委托人所追求的终极目的。从委托人不能解读的专门问题到被鉴定人解读后的鉴定结论。这是一个对证据的认识过程。而这一认识过程的结果也是证据形式之一。对于鉴定结果．委托人必须进行评价和判断。评断的主体包括委托人和有程序决定权的人。评断对象是鉴定结论。这里的结论包括了整个鉴定报告。在评断时从证据能力和证明价值两个方面进行。同时。还必须对被鉴定的实物证据的证据能力和证明价值先行评断。     

植物物证检验及其在法庭科学中的应用

在一些刑事案件中 ,检验案犯无意间带走或留在现场的植物叶片、果实、斑汁、花粉等植物物证 ,对确定嫌疑人与犯罪现场的关系 ,认定或排除嫌疑人常起到关键作用[1] 。本文作者就植物物证在司法实践中的作用及不同植物物证检验方法的应用作一综述 ,旨在使植物物证在法庭科学实践中得到充分利用 ,能为侦察破案和司法审判提供线索或证据。1　植物物证检验在法庭科学实践中的作用1 1　植物物证用于认定犯罪嫌疑人的证据在刑事案件中 ,对从嫌疑人处提取的植物物证和从犯罪现场提取的植物物证 ,通过植物种类的鉴别和同一认定 ,认定嫌疑人 ,从而为审…     

物证鉴定中的物证污染问题

物证污染是影响物证鉴定结果的最重要因素之一,它会损害物证鉴定结论质量甚至造成错误的鉴定结论。随着以法医DNA检验为代表的物证鉴定技术检验灵敏度的提高,物证污染出现的可能性及其造成的危害程度都显著增加。物证污染有多种形式和来源,可能发生在犯罪现场或实验室。采取适当的污染防范措施可以有效降低物证污染发生的可能性,及时监测和发现物证污染可以将污染造成的危害降到最低。     

浅谈鉴定结论的证据作用

1 鉴定结论的证据特征《刑事诉讼法》、《民事诉讼法》均将鉴定结论作为一种诉讼证据.法律意义上的鉴定结论是指:鉴定人根据侦查机关、检察机关、审判机关的指派或聘请,运用自己的专门知识和技能,就案件中某个专门性问题进行鉴定后得出的书面意见.鉴定结论具有所有证据共有的基本特征,即客观性、内在关联性和合法性.客观性是指鉴定结论必须是客观事实的反映.内在关联性是指作为诉讼证据的事实材料与本案有内在的联系,表现为证据的事实材料本身就是待证事实的组成部分,或作为证据的事实材料虽不是待证事实的组成部分,但与待证事实有直接或间接的联系,并能够为待证事实提供证明情况.合法性是指实体法所要求的特定形式,如书面形式、公证证明形式;证据的收集、保全、鉴定和判断必须符合诉讼法和其他法律规定的程序.鉴定的过程、使用的方法本身是科学客观的,鉴定结果自然具有客观性.鉴定人是完全按照委托人的要求进行各项技术鉴定的,鉴定结论必然与所证明的案件事实有内在关联性.鉴定结论的合法性主要体现在,出具结论的部门为法定部门或指定部门;鉴定人具有鉴定资格,是有专门知识和技能的自然人.用于鉴定的物证材料的提取、收集符合法定程序;出具鉴定结论的形式为书面形式.     

关于刑事诉讼证据理论和实用的几个问题

一、刑事诉讼证据的基本理论及司法实践中研究的重点我国《刑事诉讼法》规定:“证明案件真实情况的一切事实,都是证据。”这一规定表明,刑事诉讼证据具有客观性和关联性两个基本属性。法定的刑事诉讼证据有6种:1.物证、书证;2.证人证言;3.被害人陈述;4.被告人供述和辩解;5.鉴定结论;6.勘验、检查笔录。在司法实践中,重点研究的是运用广泛的物证、书证和鉴定结论。物证是指能证明案件事实的物品和痕迹。它是以物品的外部特征和物质属性来证明案情的,如尸体、凶器、毛发、精斑、血痕等。大部分物证通过鉴定,可以与特定物或特定的人身进行同一认定,其证明力较大。     

司法鉴定在诉讼中如何回归为科学判断

鉴定结论之所以能证明案件真实,程序规范和实体真实是其必备的两个方面。其中鉴定的实体真实是基础,鉴定的程序规范是保障。依据不完整的鉴定资料作出的鉴定结论在证据能力上存有瑕疵,必然会弱化其证明力。证据规则的引入,证明标准的正确理解与证明价值的重新认知与选择,一定程度扩大了传统“鉴定结论”的外延。法官和诉讼当事人对鉴定结论的审查和质证、认证,并不仅局限于结论本身,而应围绕该结论形成的主体、程序、材料来源以及具体依据展开,鉴定结论的客观性、关联性和合法性才能确实得以保障,鉴定结论才能回归为“科学判决”。     

Regularities in Eyewitness Identification

What do eyewitness identification experiments typically show? We address this question through a meta-analysis of 94 comparisons between target-present and target-absent lineups. The analyses showed that: (a) correct identifications and correct-nonidentifications were uncorrelated, (b) suspect identifications were more diagnostic with respect to the suspect’s guilt or innocence than any other response, (c) nonidentifications were diagnostic of the suspect’s innocence, (d) the diagnosticity of foil identifications depended on lineup composition, and (e) don’t know responses were nondiagnostic with respect to guilt or innocence. Results of diagnosticity analyses for simultaneous and sequential lineups varied for full-sample versus direct-comparison analyses. Diagnosticity patterns also varied as a function of lineup composition. Theoretical, forensic, and legal implications are discussed.     

Taking the bait: interrogation questions about hypothetical evidence may inflate perceptions of guilt

ABSTRACT

During suspect interviews, police will sometimes ask about hypothetical incriminating evidence to evoke a cue to deception – a technique known as a bait question. Previous research has demonstrated such questions can distort peoples’ memory for what evidence exists in a case. Here, we investigate whether such memory distortion can also cause people to see the suspect as more likely to be guilty. Across three experiments, we find exposure to bait questions led to participants hold inflated views of a suspect’s guilt. Further, we demonstrate bait questions cause reliable, robust memory distortion, leading participants to believe non-existent, incriminating evidence exists. However, we found no evidence to support the speculated mechanisms for this inflation – namely, (1) that source monitoring errors could lead people to misremember false evidence as real evidence and (2) that bait questions provide ‘key evidence’ to fill in the gaps of an incomplete theory of a case. In sum, bait questions have the problematic potential to shift jurors towards guilty verdicts. We suggest future research directions on bait questions, including the need for different designs to clarify why bait questions inflate guilt, and recommend practitioners avoid the use of bait questions.     

Perceptions of children during a police interrogation: Guilt,confessions, and interview fairness

Abstract

Jurors are often provided with confession evidence and must determine whether the confession was true, false, coerced, or voluntary. As more juveniles are tried in adult criminal court, jurors must increasingly make these determinations about minors’ statements. In this study, mock jurors read an actual interrogation of a child suspect that included confession evidence, and then provided judgments regarding the coerciveness of the interrogation, the child's and police's knowledge and behaviors, and guilt. Child age (11 versus 14 years) and gender were manipulated and examined in relation to participant gender and pre-existing sympathy levels for juvenile offenders. Factors external to the suspect – participant gender and sympathy for juvenile offenders – interacted with child suspect factors to influence perceptions of the child, the interrogation, and guilt. When multiple factors were considered, perceptions of suspect credibility and police fairness were the strongest predictors of guilt and perceived culpability. The findings have implications for decision-making in cases involving juvenile defendants and confession evidence.     

Rapid and nondestructive analysis of lipstick on different substrates using ATR-FTIR spectroscopy and chemometrics

Lipstick can be an important piece of evidence in crimes like murders, rapes, and suicides. Due to its prevalence, it can be an important corroborative evidence in crime reconstruction. The analysis of such evidence can provide an evidentiary link between the suspect, the victim, object, or the crime scene. We report the use of nondestructive ATR-FTIR spectroscopy combined with chemometrics for the classification of 10 brands of lipsticks with nine samples each. Chemometric method of partial least square-discriminant analysis (PLS-DA) has been employed to interpret the data and classify the samples into their respective classes. The PLS-DA model provides an AUC figure above 0.99 in all brands except one; for which it is slightly less at 0.94. We have also tested the traces of these lipstick samples on different substrates treating them as unknowns in the already trained PLS-DA model. 100% of the samples on nine substrates viz. a cotton, nylon, plastic, dry tissue, denim (blue jeans), wet tissue, nitrile gloves, white paper, and polyester were correctly attributed to their source brand. In conclusion, the results suggest that ATR-FTIR combined with the chemometrics is a rapid, nondestructive, and accurate method for the discrimination and source attribution of lipstick. This study has potential for use in actual forensic casework conditions.     

Knowing when the camera lies: Judicial instructions mitigate the camera perspective bias

Purpose. Videotaped confession evidence elicits harsher evaluations against a defendant if initially recorded with the camera focused primarily on the suspect, compared with other presentation formats. Unfortunately, most videotaped confession evidence employs this biasing suspect‐focus camera perspective format, leaving defendants with no recourse. The present study examined the utility of judicial instructions in mitigating the effects of the camera perspective bias on individual juror verdicts. Methods. Through random assignment, 156 mock jurors did or did not receive explicit instructions to correct for the camera perspective bias prior to viewing a video recording of an authentic true or false confession. Results. As expected, mock jurors who received instructions to correct for the camera perspective bias reported more lenient judgments of confessor guilt after viewing a suspect‐focus confession recording compared to those who did not receive such instructions. However, this relative leniency emerged only in response to false, and not true, confessions. Conclusions. Results demonstrated that judicial instructions used in the present research mitigated the effect of camera perspective on mock‐juror judgments of suspect guilt.     

Unanalyzed evidence in law-enforcement agencies

Research Summary This study investigated forensic evidence processing in a nationally representative sample of state and local law-enforcement agencies (n = 3,153). For a 5-year period, agencies reported that 14% of all unsolved homicides (an estimated 3,975 cases) and 18% of all unsolved rapes (an estimated 27,595 cases) contained forensic evidence that had not been submitted to a forensic crime laboratory for analysis. Approximately 40% of these unanalyzed homicide and rape cases were reported to have contained DNA evidence. The lack of a suspect in the case was the most frequently cited reason for not submitting forensic evidence for analysis. Policy Implications Despite an increased diffusion of knowledge regarding the value of forensic evidence in the prosecution and defense of criminal cases, the investigative capabilities of forensic science are not being realized by law enforcement. Additional training for law enforcement on the use of forensic science to develop investigative leads is critical, as is the creation of departmental policies that prioritize and streamline the analysis of forensic evidence for homicide and rape cases—even in “no-suspect” cases. Ensuring adequate resources and information sharing for forensic processing especially of violent crimes, is also critical.     

Screen-printing ink transfer in a sexual assault case

Yellow plastic-like particles were discovered on the clothing and body of a sexual assault victim. These particles were later associated to an athletic jersey with flaking yellow screen-printed numbers and letters, worn by the suspect. Depending on its intended substrate, screen-print ink can vary in color and composition. Particles dislodged from screen-printed garments may exhibit fabric impressions. Screen-printed clothing, commonly encountered in forensic casework, should be viewed as a potential source of trace evidence.     

Fatal suffocation by rubber balloons in children: mechanism and prevention

The increase in the use of photographs on individual identification credentials such as driving licences, credit cards, security passes and passports has led, for the purpose of criminal activities, to the falsification of genuine documents bearing photographs of the perpetrating criminal. These photographs may be used as valuable physical evidence when compared with known photographs of a suspect as they form somewhat of a signature of the suspect that is left behind on the evidence. The comparison of ID photographs requires the cooperation of two predominantly visual disciplines; forensic photography and morphological anatomy. This paper describes a photographic technique which allows accurate anatomical measurement and tracing of facial features, which allows direct physical comparison of ID document images.     

Handling manipulated evidence

Bayesian Networks have been advocated as useful tools to describe the relations of dependence/independence among random variables and relevant hypotheses in a crime case. Moreover, they have been applied to help the investigator structure the problem and evaluate the impact of the observed evidence, typically with respect to the hypothesis of guilt of a suspect. In this paper we describe a model to handle the possibility that one or more pieces of evidence have been manipulated in order to mislead the investigations. This method is based on causal inference models, although it is developed in a different, specific framework.