Handwriting evidence evaluation based on the shape of characters: application of multivariate likelihood ratios

A novel Bayesian methodology has been developed to quantitatively assess handwriting evidence by means of a likelihood ratio (LR) designed for multivariate data. This methodology is presented and its applicability is shown through a simulated case of a threatening anonymous text where a suspect is apprehended. The shape of handwritten characters a, d, o, and q of the threatening text was compared with characters of the true writer, and then with two other writers, one with similar and one with dissimilar characters shape compared to the true writer. In each of these three situations, 100 draws of characters were made and the resulting distributions of LR were established to consider the natural handwriting variation. LR values supported the correct hypothesis in every case. This original Bayesian methodology provides a coherent and rigorous tool for the assessment of handwriting evidence, contributing undoubtedly to integrate the field of handwriting examination into science.     

Forensic identification science evidence since Daubert: Part II--judicial reasoning in decisions to exclude forensic identification evidence on grounds of reliability

Many studies regarding the legal status of forensic science have relied on the U.S. Supreme Court's mandate in Daubert v. Merrell Dow Pharmaceuticals Inc., and its progeny in order to make subsequent recommendations or rebuttals. This paper focuses on a more pragmatic approach to analyzing forensic science's immediate deficiencies by considering a qualitative analysis of actual judicial reasoning where forensic identification evidence has been excluded on reliability grounds since the Daubert precedent. Reliance on general acceptance is becoming insufficient as proof of the admissibility of forensic evidence. The citation of unfounded statistics, error rates and certainties, a failure to document the analytical process or follow standardized procedures, and the existence of observe bias represent some of the concerns that have lead to the exclusion or limitation of forensic identification evidence. Analysis of these reasons may serve to refocus forensic practitioners' testimony, resources, and research toward rectifying shortfalls in these areas.     

应用马氏距离综合评价笔迹特征质量

在笔迹检验中,应用马氏距离的方法对笔迹特征进行量化处理,根据笔迹特征的综合性分析,能快速、准确地对检材与样本的符合程度进行评断,从而优选出与检材最为接近的样本材料,为认定嫌疑人提供科学依据。     

阿拉伯数字笔迹检验探析

随着社会的发展,在各类经济、刑事及民事纠纷案件中涉及对阿拉伯数字笔迹进行鉴定的案件呈逐年上升趋势。阿拉伯数字作为一种常见的书写符号,具有其自身的独特特点。通过分析阿拉伯数字笔迹的特证,并对其检验难点及检验方法要点等问题进行分析阐述,进一步充实与完善对此类数字符号笔迹的检验方法。     

Visualizing Indented Writing on Thermal Paper by the Controlled Application of Heat

Indented writing on thermal paper made with either one, two, or three sheets of paper above the thermal paper has been visualized by the controlled application of heat to the thermal paper at temperatures below the paper's normal color change temperature. Indentations created by applying a variable pressure to a steel letter stamp showed that, with one sheet above the thermal paper, indentations were more visible at lower pressures than with either two or three sheets above. Handwriting from 20 volunteers produced indented writing graded with most of the text clear and easy to read for all samples with one sheet above, half the samples with two sheets above and eight samples with three sheets above. Comparison with ESDA showed that, with three sheets above, there was a statistically significant difference (p < 0.01), with heating producing more samples than ESDA with most of the text clear and easy to read.     

老年人笔迹变化的形成原因和特点

世界人口老龄化发展的历史表明,人口老龄化对人类社会生活的各个方面都会产生重大的影响。因此,研究老年人笔迹特点及其变化规律对于老年人笔迹鉴定具有理论指导意义和实用价值。根据老年人笔迹变化的形成原因和对老年人笔迹的实验统计分析,包括横向分析、纵向分析、病理性变化的分析,得出了老年人笔迹的特点。     

刍议计算机辅助笔迹检验系统运用中的综合评断

随着计算机技术的不断发展,计算机技术在笔迹检验中得到广泛运用。但是,在尚未实现计算机“自动化”进行笔迹检验之前,综合评断仍然在计算机辅助笔迹检验系统运用中起着重要的不可忽视的作用。     

关于同一人不同书写速度笔迹变化规律的研究

在笔迹鉴定中,经常会遇到由于检材与样本的书写速度不同,造成二者间的可比性差,给检验和鉴定带来较大的困难。因此,对同一人用不同书写速度造成笔迹变化的规律进行全面、系统的研究,很有必要。文章通过对不同性别、不同年龄、不同职业、不同文化的人群书写速度变化笔迹特征存在的稳定性和可变性进行了统计分析,总结出了同一人速度变化笔迹的规律。研究结果表明,同一人不同书写速度变化的笔迹既具有不变的稳定性特征,也具有可变性特征。     

数码电子显微镜鉴别手印和字迹形成顺序

对手印和书写字迹形成顺序的检验,是当前刑事科学技术中的研究热点。文章通过对当前采用一种新颖数码电子显微镜鉴别手印和字迹形成顺序的研究,认为这种检验方法无论是鉴定结果的准确性、检验的宽度、快捷和简便程度都较以往的检验方法有较大的进步,特别是它具有能和电子计算机简单连接、方便信息图像存储的特性,更使数码电子显微镜日益成为鉴定中不可或缺的工具。     

写字机摹仿书写笔迹检验探究

写字机实质是一种简易的数控装置,根据事先编排好的字库,转换为矢量图。该矢量图数据通过电子元件控制书写工具X、Y、Z轴移动路径从而在固定的纸张上留下接触的墨痕。目前写字机在淘宝上多有销售,不可避免地会被不法分子利用。从写字机摹仿书写笔迹的原理出发,结合对其摹本的比较,可探究写字机摹仿书写笔迹的特征,从而发现写字机摹仿书写笔迹与一般摹仿笔迹的区别。实验显示,检验涉嫌写字机摹仿书写笔迹的基本要点是:了解案情是否具有写字机摹仿书写的情形条件;分析检材笔迹笔痕宽窄、深浅是否均匀;与临摹、套摹笔迹存在本质差异;追根溯源寻求相关证据支持。