对变形手印的检验鉴定

笔者结合实际工作中的体会,对手印变形产生机理、变形手印的特征及检验进行探讨。1变形手印产生机理[1]1.1手指、掌自身的生理结构特点是变形手印产生的基础手指、掌是人体中的重要“功能体”部分,由内向外依次由骨骼、肌肉、脂肪组织、皮肤共同构成;而形成手印的皮肤是一种具有特殊纹线的皮肤软组织,其皮下有较为发达的脂肪层,当大小不同的力作用时皮肤富有较强的弹性和伸展性,因此极易使手指、掌的纹线产生“自由移位”现象,引起特征的各种变化。加之,由于手指外形呈半球面体,故更加强了手指皮肤移位的能力。1.2手指、掌与客体间的机械作…     

现场模糊、残缺手印案例的分析与检验

现场模糊手印是指在普通光线下虽可见手印印痕,但不易或不能分辨乳突线与犁沟线痕及其特征的一种现场手印;而残缺手印是指现场手印中仅出现手指、指节和手掌某一小部分的手印。对犯罪现场模糊、残缺手印作科学分析与检验,有助于侦查部门准确判断案件性质、犯罪人数、作案过程、个人特点等;根据其特殊规律可缩小样本手印的搜集范围,帮助我们确定侦查方向、明确比对重点对象、加快对指纹库的查询速度；为案件诉讼提供科学的鉴定意见。     

浅议现场手印分类的意义

指纹作为物证之首,对现场手印进行分类有利于手印的保护、显现、提取、分析检验等,充分发挥指纹技术在侦查破案、打击犯罪中的特有优势和作用。     

用手印快速比对检验程序应注意的问题

在指纹查询比对工作中通常遇到的情况是，一枚现场手印要与几十枚甚至上百枚样本手印进行比对．或一名嫌疑人十指指纹要与上百枚现场手印进行比对，而不是一枚现场手印对一枚样本手印的一对一的检验，这就需要建立一个科学、准确、快速有效的比对检验程序，以便迅速准确地发现相同的手印，满足大量实际工作的需要。     

闪光灯照相用于现场手印

对现场手印进行综合分析,结合勘查实践,对几类常见现场手印如何运用闪光灯照相提取进行了可行性探讨,具有实用性,可操作性.     

现场手印变形的原因和规律初探

在现场勘查时，所发现的手印多是残缺变形印痕，给检验工作带来一定的困难，甚至给案件的侦破工作造成疑难。所以，研究分析手印的各种变化原因，是手印检验工作有待于进一步解决和掌握的问题。笔者就部分案例中变形手印的分析和利用谈一些见解。同一人手指在不同条件下所形成的印痕，一般是出现“形变”和“量变”的变化。常见的现场指印有残缺、模糊，可称量变；重叠、变形，有时两者共存，称之形变。根据手印变化的原因可分：自身的变化；承受客体表面物质的变化；机械作用的变化；手印形成物质条件的变化；显现加工处理的变化；自然条件…     

浅议现场手印的保护

现场手印在犯罪现场勘查中因能直接认定人身而被视为最有价值的证据之一,因此对对现场手印的保护对于现场勘查有着重要的意义。     

硅钢片上油质手印的现场拍照法

在盗窃变压器和电动机补偿器铜芯的案件中，犯罪分子作案时往往容易在硅钢片上遗留油质减层手印。这类手印纹线反差微弱，直接拍照效果很不理想，并且因为硅钢片上油质较厚，在运输过程中以及保存期间，油质容易流动而损坏手印纹线，给勘查提取工作带来很大的麻烦。在实际工作中，笔者采用“背面烘烤拍照法”和“５０２”与粉末配合显现拍照法在现场拍照提取，节省了大量人力物力，且拍摄效果很好，现将这两种拍照方法介绍如下：１背面烘烤拍照法将留有纹线的一面朝上，在硅钢片背面与纹线对应部位用火烘烤。烘烤时可以用打火机（最好是防风…     

运用光谱成像技术检验拍摄手印

光谱成像（Spectral Imaging）是通过光谱成像设备记录被检验物体在一定光谱范围内密集均匀分布的多个窄波段单色光的反射光亮度分布或荧光亮度分布，形成由许多单色光影像构成的光谱影像集。围际上，澳大利亚联邦警察于2003年9月在法庭科学杂志发表了第一篇利用光谱成像技术应用于法庭科学进行手印检验的技术论文，随后，美国FBI实验室、新西兰奥克兰大学的法庭科学实验室也陆续有相关的应用报道。     

利用手印DNA破获1例杀人案

1 案例资料 1．1 案情简介 2008年4月12日凌晨,湖北省阳新县白沙镇某辖区发生一起由入室盗窃转化为抢劫杀人的案件,犯罪嫌疑人攀爬水管、翻铝合金窗户入室,趁受害人熟睡之机,大面积翻动,后因动作过大,惊醒受害人王某（女,36岁）,因王某反抗、喊叫,犯罪嫌疑人用随身携带的匕首将王杀害。经现场勘查,犯罪嫌疑人先撬防盗网的窗齿,后推开铝合金窗户进入室内,在室内的地面上可见用棉布包扎皮鞋形成的减层足迹,     

指纹鉴定标准研究

通过对国内学术界关于指纹鉴定标准构建的几种思路的分析,经综合比较,选择符合点＂数量＂思路作进一步探讨。在简要分析国外指纹鉴定＂数量＂标准研究概况基础上,尝试提出新的＂指纹特征组合概率计算模型＂,并以概率计算方式论证了8个符合点作为鉴定标准的合理性,由此得出一些对指纹鉴定工作可能有现实意义的结论。     

基于深度学习的指纹自动识别技术

本文从学科领域入手,对指纹自动识别技术在发展过程中受人工智能技术影响所产生的新变化进行简述。指纹识别技术作为一种计算机应用技术,其发展与计算机科学的新技术密切相关。人工智能技术,特别是基于深度学习的图像技术的发展使指纹识别算法开启了全新的模式。本文将人工智能在指纹领域的发展分成三个阶段,并对当前所处的第二阶段的发展趋势进行了分析。基于深度学习的指纹识别技术使用图像特征而不是传统细节点特征的方式,改变了法庭科学领域对指纹识别的认知。本文重点对深度学习技术在指纹识别方面的应用模式和典型的技术方法进行了论述,给出了基于深度学习的指纹识别技术方案图,对技术方案中的网络模型设计等重要步骤逐一进行了说明,提出了图像处理、降维等几个需要重点攻坚的技术环节。对现有的可为指纹识别借鉴使用的深度网络模型进行了介绍,如:卷积神经网络、自编码器网络。最后对人工智能指纹识别算法与传统算法的性能进行了对比。     

基于指纹图像清晰度提取和评估指纹中心点的方法

基于指纹图像清晰度提取和评估指纹中心点的方法是对传统的指纹中心点提取方法的改进,能够加快提取速度、改善提取效果,从而使指纹中心点评估参数更加客观、准确,并达到量化评估的目的。     

指纹鉴定标准及鉴定结论概率化研究

指纹鉴定标准是指纹鉴定理论的核心内容之一.指纹鉴定理论和实践中形成的最低特征数量标准、质量—数量标准、面积—质量量化标准、拓扑学方法和标准、形态学方法和标准等均有其局限性.运用统计学理论和贝叶斯定理建立指纹鉴定结论概率化方法和评价标准,不仅在理论和实践上具有必要性和可行性,而且也可以避免指纹鉴定标准之争,使指纹鉴定从经验走向科学.通过统计每枚指纹平均细节特征数量和每类特征的出现率,可以计算出两枚指纹匹配的概率值,进而对概率结论的可靠性作出分析评断.     

Fingerprint error rate on close non‐matches

The accuracy of fingerprint identifications is critically important to the administration of criminal justice. Accuracy is challenging when two prints from different sources have many common features and few dissimilar features. Such print pairs, known as close non‐matches (CNMs), are increasingly likely to arise as ever‐growing databases are searched with greater frequency. In this study, 125 fingerprint agencies completed a mandatory proficiency test that included two pairs of CNMs. The false‐positive error rates on the two CNMs were 15.9% (17 out of 107, 95% C.I.: 9.5%, 24.2%) and 28.1% (27 out of 96, 95% C.I.: 19.4%, 38.2%), respectively. These CNM error rates are (a) inconsistent with the popular notion that fingerprint evidence is nearly infallible, and (b) larger than error rates reported in leading fingerprint studies. We conclude that, when the risk of CNMs is high, the probative value of a reported fingerprint identification may be severely diminished due to an elevated false‐positive error risk. We call for additional CNM research, including a replication and expansion of the present study using a representative selection of CNMs from database searches.     

论司法鉴定中的指印鉴定

随着司法改革的不断发展,司法鉴定的科学性、公正性、中立性越来越受到人们关注,而在司法鉴定中,指印鉴定在检材、样本方面与公、检、法所受理的鉴定有所不同,应从“吃透”检材,寻找确定特征,注意字迹对纹线的影响,鉴定结论和提高鉴定人员综合素质等方面做好鉴定工作。     

Suspect/Foil Identification in Actual Crimes and in the Laboratory: A Reality Monitoring Analysis

Four reality monitoring variables were used to discriminate suspect from foil identifications in 183 actual criminal cases. Four hundred sixty-one identification attempts based on five and six-person lineups were analyzed. These identification attempts resulted in 238 suspect identifications and 68 foil identifications. Confidence, automatic processing, eliminative processing and feature use comprised the set of reality monitoring variables. Thirty-five verbal confidence phrases taken from police reports were assigned numerical values on a 10-point confidence scale. Automatic processing identifications were those that occurred “immediately” or “without hesitation.” Eliminative processing identifications occurred when witnesses compared or eliminated persons in the lineups. Confidence, automatic processing and eliminative processing were significant predictors, but feature use was not. Confidence was the most effective discriminator. In cases that involved substantial evidence extrinsic to the identification 43% of the suspect identifications were made with high confidence, whereas only 10% of the foil identifications were made with high confidence. The results of a laboratory study using the same predictors generally paralleled the archival results. Forensic implications are discussed.     

Eyewitness Identification in Actual Criminal Cases: An Archival Analysis

This study analyzed 271 actual police cases in order to address several prevalent issues in the eyewitness literature. Suspect identification (SI) rates were obtained for 289 photographic lineups, 258 field showups, 58 live lineups, and 66 lineup identifications preceded by earlier identifications. SI rates were assessed for 3 levels of extrinsic evidence: no extrinsic evidence, evidence of minimal probative value, and evidence of substantial probative value. The SI rates for the photographic lineups were assessed as a function of delay, same vs. cross-race conditions, witness type, and weapon presence. SI rates declined significantly over time; SI rates were significantly greater for the same-race condition. SI rates were much greater for field showups than photographic lineups, 76% vs. 48%. The SI rates for the field showups did not vary as a function of eyewitness conditions. The relation between confidence and suspect/foil identifications for the live lineups was significant and moderately high. The utility of archival identification studies for eyewitness testimony research is discussed.     

The Effect of Varying the Composition of Fingerprint Sweat Deposits on the Corrosion of Brass and Fingerprint Visibility

Corrosion of α‐phase brass by sebaceous sweat fingerprint deposits produced identifiable impressions in a majority of samples (n = 40) 4 days after deposition. Combining sebaceous with eccrine sweat yielded a greater percentage of identifiable fingerprint deposits, although this increase was not statistically significant. Production of identifiable fingerprints from eccrine sweat deposits was dependent on the sampling time of year with deposits taken during summer months giving similar percentages of identifiable fingerprints to sebaceous deposits. A statistically significant positive correlation was found between elapsed days after deposition and identifiable eccrine (ρ = 0.787, p < 0.05), sebaceous (ρ = 0.724, p < 0.05), and eccrine/sebaceous mixture (ρ = 0.908, p < 0.01) fingerprints deposited during summer months. The summer increase in the percentage of identifiable eccrine sweat deposits was statistically significant compared to winter eccrine deposits (p < 0.0001). Observations were consistent with results obtained from artificial sebaceous and eccrine sweat.     

"轻罪"之法价值取向与人身权利保护

从中外关于"轻罪"的不同语境及其确定涵义论起,指出国外学者视角上的中国的"轻罪",多指中国现行劳教体制所调控的诸种行为.进而阐述了近年来中国学界关于劳教制度存废之争的实质,指出改革论与废除论者本质上都是既要从形式上、又要从实质上改革现行劳教体制下的程序与实质不正义问题.因而改革论与废除论之间并无本质区别.进而,在阐述并评析了多种关于现行劳教体制的改革观之后,指出要解决劳教制度改革方案之争,须先行解决有关设计方案的价值取向问题.而各种改革之争,实质是功利主义优位还是人权保障优位之争.主张在不危及国家、社会根本利益前提下的"人权保障优位"的法价值观.指出单纯的"功利主义至上",势必导致功利而不公平、不公正,甚而有违法治的正义原则.而作为正义基本蕴涵的公民在一定社会经济条件下的最大限度的公平与自由,正是人权保障得以实现的基本路径和期寻方向.因而人权与正义并不必然冲突.惟其如此,在一定平衡条件下的"人权保障优位"的法价值观,值得作为我们重塑有关"轻罪"方案时的立法价值取向.在此基础上,进一步论证了改革现行劳教体制的法理思考和立法构想.