专业性练习摹仿签名笔迹鉴定的实验研究

目的本文通过实验对具有一定笔迹鉴定专门知识与不具备笔迹鉴定专门知识的人的练习摹仿签名笔迹进行实验分析研究。方法对两类人在练习的不同阶段形成的练习摹仿签名笔迹特征的一般状态表现,以及对其笔迹特征的形成、变化原因、鉴定价值分别进行了论述,并总结出其变化规律。结果为不同种类的练习摹仿签名笔迹的鉴定提供一定的识别和特征分析、评断的参考依据。     

摹仿笔迹的检验

摹仿书写是学习写字、练习书法的必由之路,摹仿笔迹是一种常见的笔迹类型。摹仿笔迹书写人的笔迹特征暴露少,被摹仿人的笔迹特征体现较多,鉴定难度较大,因此常常被用于仿造他人的签名、单据、契约、信件、传单。笔者经过多年鉴定实践,认为在摹仿笔迹的鉴定中摹仿的确认是关键,在分析比对过程中,应注重从整体上把握笔迹特征,正常书写字迹一般气脉贯通、气势相连,而摹仿书写的字迹呆板生硬,缺乏神韵。     

练习摹仿笔迹特征鉴定价值分析及同一认定条件

练习摹仿笔迹鉴定是笔迹鉴定中比较难的一种，但在司法实践中又比较常见，在借据、收据、签名、批示笔迹的书写上常常被作案人采用。本文对练习摹仿笔迹的特征及其鉴定价值进行了分析，并总结出作为一般规律的识别要素，以期对练习摹仿笔迹的鉴定提供一定的参考依据。     

练习摹仿加复写套摹笔迹的识别与检验

练习摹仿加复写套摹笔迹是指作案人为逃避打击、嫁祸于人,先比照被摹仿人笔迹进行临摹仿写,再选择被摹仿人适当样本笔迹复写套摹成作案材料,从而形成与被摹仿人字迹十分相似的笔迹。这种复合伪装的手段是摹仿字迹的高级形式,极具迷惑性。如不对检材作科学深入地分析研究,很容易使检验工作误入岐途。笔者结合实际案例,试对这种不常见的伪装手段的识别与检验进行初步探讨。1　案例简介1 995年9月30日,某金融信用社在与某银行进行月结算时,发现一笔非本社经办却手续齐全的捌万肆仟元汇票委托联单,这笔申请汇往“天津”的“货款”已从天津支付结…     

浅谈不显露型习摹笔迹的辨识及检验技巧

以前，每当提及摹仿笔迹，便会立即将“形快实慢、运笔生涩、弯曲抖动、停顿重描”等征兆与摹仿二字划上等号。然而事实上，在科学技术高速发展的今天，随着人们书写水平的普遍提高，一种不显露型的练习摹仿笔迹的出现率正逐渐增多。有相当数量的摹仿者脱离常规的仿写模式，经过临摹与记忆摹仿等多种手段的综合练习，使摹仿笔迹蒙以“书写自然、运笔流利”的假象充斥于伪造证据之中。此种习摹笔迹不仅会使探案人员陷入迷宫，而且极易导致执法机关错鉴误判，对此我们决不可掉以轻心。为了及时有效地识别习摹笔迹，确保摹仿字检案质量，笔者拟…     

浅析摹仿签名笔迹鉴定

摹仿签名笔迹检验是笔迹检验的难点,认定签名摹仿人更是难中之难;笔者通过正确确定签名笔迹的真伪,从签名笔迹的概貌特征和细节特征之中运用辩证的观点正确认定摹仿人。     

认定套摹人方法初探

认定套摹人方法初探程连栋套摹笔迹，是指摹仿人在他人的笔迹上，通过透视法、复写法或抑压法，逐笔逐字地进行描摹。由于是按被摹仿笔迹进行套描，这种摹仿笔迹和被摹仿人的笔迹非常相似。较难区别，特别是对套摹人的认定就更加困难。在文件检验工作中，认定套摹人虽然十...     

自我摹仿笔迹鉴定研究

自我摹仿笔迹是一种新出现特殊的摹仿笔迹,由于其自摹仿的特殊性而使得鉴定人容易产生识别与判断的错误。为了完善摹仿笔迹鉴定的理论以及正确的鉴定自我摹仿笔迹,应结合案例与实验,弄清自我摹仿笔迹的形成机制、特点,改进识别的方法、完善鉴定规范。     

再看摹仿签名笔迹鉴定

由于签名笔迹字数少、可摹仿性强的特点,长期以来,摹仿签名笔迹鉴定始终是笔迹鉴定的难点。笔者从不同类型的摹仿方法出发,讨论不同方法下摹仿签名笔迹的特点,总结其特征规律。同时要重视笔迹鉴定过程中了解相关案情,为识别是否存在摹仿现象提供线索。在此基础之上,对比摹仿签名笔迹特征的变化规律,并从摹仿签名笔迹特征反映构成方面系统性地进行鉴定,鉴别是否存在摹仿签名的情况。通过撰写此文,以期对摹仿签名笔迹鉴定实务具有借鉴意义。     

摹仿笔迹的系统分析

本文从系统的角度分析了摹仿笔迹的形成机制与正常笔迹的区别，分析了摹仿笔迹的特征，并提出了检验摹仿笔迹的对策。     

Are expert penmen better than lay people at producing simulations of a model signature?

Although forensic signature examination is considered to be an identification science, it is a theoretical possibility that an individual may learn to forge another person's signature that is free from indications of simulation behaviours. This proposition was tested in a signature blind trial that was administered to 42 forensic handwriting examiners (FHEs). Participants expressed opinions on the authorship of 100 questioned signatures. The questioned signatures comprised a mixture of genuine, disguised and simulated signatures. Calligraphers formed part of the population of individuals who provided simulated signatures for the trial. A total of 3100 opinions were expressed of which 1254 were correct, 224 misleading and 1622 were inconclusive. Of the opinions expressed regarding the simulated signatures, the misleading score for the calligraphers' forgeries were approximately four times that of the lay persons' forgeries. These results provide strong evidence in support of the proposition that calligraphers are more skilled at simulating signatures than are lay people and can produce forgeries that some FHEs have difficulty detecting.     

The potential of collaborative learning as a tool for forensic students: Application to signature examination

Transferring theoretical knowledge to practical skills remains a big challenge in forensic science, especially in questioned documents. The examination of handwriting and signatures requires years of practice to develop the necessary skills. While students (and to some extent the general population) often have the impression that it is easy to differentiate handwriting from different persons, in practice, particularly when dealing with simulated signatures, there is a high risk of reaching a wrong conclusion when questioned document experts do not use a systematic approach and/or are not sufficiently experienced (see for example the famous French Dreyfus case). Thus, a novel teaching approach, based on collaborative learning, has been introduced in a theoretical handwriting class to improve the students’ theoretical knowledge, and additionally make them aware of the limitations of their practical skills and give them tools to improve them in their future practice. Through five activities, the students took the roles of victims, forgers, teachers and experts and created their own learning materials (i.e. signatures and mock casework). During those interactive activities, they learned to describe their signature’s characteristics, intra-variability and complexity, and thus evaluate their own signature’s vulnerability (as potential victims). They learned techniques to simulate signatures and detect the resulting forgeries’ characteristics (in the role of forgers). In the role of teachers, they prepared mock casework scenarios and gave feedback to their colleague’s examination of the produced material. As experts, they carried out signature examination as they would in a proficiency test and were exposed to the difficulties an actual expert may encounter in practice. The evaluation of this novel teaching scenario was very positive, as students learned more extensively the possibilities and limitations of signature comparison. They were more active and motivated in their learning experiences. The teaching team also had an improved experience. Some students complained of an increased workload and imprecise instructions. Improvements were tested and are discussed in this paper.     

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.     

Investigating forensic document examiners’ skill relating to opinions on photocopied signatures

Many forensic document examiners are hesitant to express authorship opinions on photocopied handwriting as the photocopying process results in less feature information than original writing. This study aimed to test the accuracy of 15 examiners' opinions regarding whether photocopied questioned signatures were genuine or simulated. Each examiner received the same set of original signature exemplars, from one individual, and a set of eighty questioned photocopied signatures comprising of genuine and simulated signatures. The overall misleading (error) rate for the grouped examiners' opinions was 0.9% providing strong evidence that examiners can make accurate observations regarding the authorship of non-original handwriting.     

An insight into forensic document examiner expertise for discriminating between forged and disguised signatures

It has previously been shown that forensic document examiners (FDEs) have expertise in providing opinions about whether questioned signatures are genuine or simulated. This study extends the exploration of FDE expertise by evaluating the performance of eight FDEs and 12 control subjects at identifying signatures as either forgeries or the disguised writing of a specimen provider. Subject eye movements and response times were recorded with a Tobii 1750 eye tracker during the signature evaluations. Using a penalty scoring system, FDEs performed significantly better than control subjects (t = 2.465, p = 0.024), with one FDE able to correctly call 13 of the 16 test stimuli (and three inconclusive calls). An analysis of eye movement search patterns by the subjects indicated that a very similar search strategy was employed by both groups, suggesting that visual inspection of signatures is mediated by a bottom up search strategy. However, FDEs spent greater than 50% longer to make a decision than the control group. The findings are suggestive that for some stimuli FDEs can discriminate between forgeries and disguises, and that this ability is due to a careful inspection and consideration of multiple features within a signature.     

一起練习记忆摹仿签名笔迹的鉴定与启示

本文通过对一起检验鉴定案例的分析,提出练习记忆摹仿的概念,并对该类案件的检验鉴定,总结出十点启示。     

汉英文字笔迹特征的比较研究

目的更深入的了解不同国家、地区,不同文种,不同文化背景下的笔迹鉴定工作者对特定文字笔迹鉴定认识的差别。方法以中英文为例,对汉字和英文的特点和笔迹特征进行比较研究。结论汉英文字的笔迹特征分类体系大体相似,并无质的差别,但是不同文字的特点决定了其笔迹特征取向与侧重、价值评断、个别特征的使用率,以及对同一人笔迹特征多样变化的认识上还是有所区别,各具特色。     

Dynamic Characteristics of Signatures: Effects of Writer Style on Genuine and Simulated Signatures

The aims of this study were to determine if computer‐measured dynamic features (duration, size, velocity, jerk, and pen pressure) differ between genuine and simulated signatures. Sixty subjects (3 equal groups of 3 signature styles) each provided 10 naturally written (genuine) signatures. Each of these subjects then provided 15 simulations of each of three model signatures. The genuine (N = 600) and simulated (N = 2700) signatures were collected using a digitizing tablet. MovAlyzeR^® software was used to estimate kinematic parameters for each pen stroke. Stroke duration, velocity, and pen pressure were found to discriminate between genuine and simulated signatures regardless of the simulator's own style of signature or the style of signature being simulated. However, there was a significant interaction between style and condition for size and jerk (a measure of smoothness). The results of this study, based on quantitative analysis and dynamic handwriting features, indicate that the style of the simulator's own signature and the style of signature being simulated can impact the characteristics of handwriting movements for simulations. Writer style characteristics might therefore need to be taken into consideration as potentially significant when evaluating signature features with a view to forming opinions regarding authenticity.     

Competency for Chinese Handwriting and Signature Examination

Chinese characters had their root some 4000 years ago and, with the growth in population, are used by over 1.3 billion people worldwide today; it is inevitable that document examiners would encounter cases involving the examination of Chinese handwriting regardless of their location. Although there are extensive studies on the examination of English handwriting in the literature, similar studies on Chinese handwriting are relatively limited. We are seeking to explore the obstacles and challenges for a document examiner who is unfamiliar with Chinese characters to apply the principles of identification and elimination of authorship described in the literature to examine Chinese handwriting, and how can these document examiners demonstrate their competency for conducting Chinese handwriting examination. This study provides a review of the literature, compares the methodology and key features in English and Chinese handwriting examination, and describes various workshops and proficiency testing programs organized to assist document examiners seeking development in Chinese handwriting and signature examination.     

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。