指印检验新方面

100多年来指印鉴定一直是犯罪侦查最有效的个体识别手段,在物证鉴定领域占据重要地位,上世纪80~90年代指印检验技术研究的重要进步更是使指印物证技术应用达到一个新的水平。最近几年指印技术研究又取得许多新进展和突破,特别是在指印显现技术和指印纹线物质成分分析方面开创了新方法和新方向,形成指印物证应用新体系,但同时在指印鉴定结论可靠性方面也出现新争议。     

指印生物遗传标记检验的研究现状与展望

综述了血指印和汗潜指印生物遗传标记的研究历史和现状,指印DNA检验面临的问题,包括现场污染,显现剂的影响,载体的影响等,并对指印DNA在法医学中的应用前景进行了展望。     

常用手枪枪弹创检验失误分析(附6例报告)

枪弹创检验不少见,特别是自80年代中期以来,仅据武汉地区统计,平均占全部尸体检验总数的3%,其中1989～1992年间高达5%,而近2年间则以霰弹枪创为主的枪伤检验占6～7%.明显的、典型的枪弹创检验并不困难,已有大量报告.但对非典型的枪弹创却容易引起人们的质疑,有时甚至导致鉴定失误.笔者总结了近5年间对常用手枪枪弹创检验失误的典型案例,对造成失误的原因进行讨论,以期达到避免失误的目的.     

The forensic examination of photographic equipment and materials

The scientific examination of cameras, negatives and photographic prints can provide valuable evidence. The methods used and examples of their value in criminal cases are given. The background and experience necessary to carry out this work is discussed.     

利用光学滤波方法提取透明薄片上的指纹

目的将透明薄片材料上的指纹看作＂位相物＂,利用阿贝-波特空间滤波实验进行显现研究;方法通过光学4f系统利用暗场法进行空间滤波,并将实验结果和刑事照相中的透射配光方法进行比较。结果该种方法透明薄片材料上微弱汗液指纹的显现取得较好的效果;结论利用阿贝-波特空间滤波实验可以显现部分透明薄片材料上的指纹,有关细节问题有待进一步研究。     

Statistical evaluation of standardized field sobriety tests

Standardized Field Sobriety Tests (SFSTs) are used as qualitative indicators of impairment by alcohol in individuals suspected of DUI. Stuster and Burns authored a report on this testing and presented the SFSTs as being 91% accurate in predicting Blood Alcohol Concentration (BAC) as lying at or above 0.08%. Their conclusions regarding accuracy are heavily weighted by the large number of subjects with very high BAC levels. This present study re-analyzes the original data with a more complete statistical evaluation. Our evaluation indicates that the accuracy of the SFSTs depends on the BAC level and is much poorer than that indicated by Stuster and Burns. While the SFSTs may be usable for evaluating suspects for BAC, the means of evaluation must be significantly modified to represent the large degree of variability of BAC in relation to SFST test scores. The tests are likely to be mainly useful in identifying subjects with a BAC substantially greater than 0.08%. Given the moderate to high correlation of the tests with BAC, there is potential for improved application of the test after further development, including a more diverse sample of BAC levels, adjustment of the scoring system and a statistically-based method for using the SFST to predict a BAC greater than 0.08%.     

Operational benefits and challenges of the use of fingerprint statistical models: a field study

Research projects aimed at proposing fingerprint statistical models based on the likelihood ratio framework have shown that low quality finger impressions left on crime scenes may have significant evidential value. These impressions are currently either not recovered, considered to be of no value when first analyzed by fingerprint examiners, or lead to inconclusive results when compared to control prints. There are growing concerns within the fingerprint community that recovering and examining these low quality impressions will result in a significant increase of the workload of fingerprint units and ultimately of the number of backlogged cases. This study was designed to measure the number of impressions currently not recovered or not considered for examination, and to assess the usefulness of these impressions in terms of the number of additional detections that would result from their examination.     

Forensic science does not start in the lab: the concept of diagnostic field tests

An attempt to improve an analytical system can focus either on the actual processing or on the input. In forensic science, much emphasis has been placed on improving laboratory procedures, as though the input is already the best that can be obtained. Means of improving the basic input have gained much less attention. Yet, it must be agreed that even the best laboratory cannot gain from an item more than has been contained in it when it arrived from the field. The detection of latent materials at the crime scene by physical or chemical techniques and the diagnostic examination of material already discovered belong to the concept of diagnostic field tests. This group also includes "mapping" for the presence of certain materials, such as latent fingerprints through the distribution of amino acids on the surface. These tests are conducted outside the laboratory, without sophisticated instrumentation, at the crime scene, the suspect's home, or elsewhere. A significant advantage of the use of diagnostic field tests is the ability to deal with "dissipating evidence" such as gunshot residue or explosive traces on the hands of suspects. If time is lost, there is a risk of losing such evidence, which is liable to deteriorate rapidly. In my presentation, I will discuss older and some newly developed forensic field tests, with specific emphasis on the Israeli experience.     

指纹特征点区域分布规律应用研究

目的 针对指纹自动识别系统评分机制所存在的局限性,探讨根据指纹特征点分布进行加权的方法.方法 通过总结大量人群指纹特征点区域分布规律,按照分布密度在计算中进行加权.结果 在对反查指纹加权计算的试验中,同一指纹加权后的分数相比其它指纹得到了提高.结论 采用此种加权机制,对于现有基‘于特征点的指纹自动识别系统准确率提高是有效的.     

茚三酮固体介质法显现不同纸张表面潜指纹

茚三酮是显现渗透性客体上潜在汗液手印的最常用方法之一,采用微量物证提取纸和茚三酮溶液有机结合制作的茚三酮固体介质可以有效避免客体表面背景着色,不容易引起纸张油墨扩散,另外避免使用的溶剂易燃。能够更便捷的显现现场指纹,并且能够突破茚三酮只能显现渗透性客体的局限,拓宽茚三酮显现客体的范围,在热敏纸上潜指纹的显现方面有独特的应用优势。     

Abandoning the common law: medical negligence, genetic tests and wrongful life in the Australian High Court

The Australian High Court recently found that the common law could allow parents to claim tortious damages when medical negligence was proven to have led to the birth of an unplanned, but healthy, baby (Cattanach v Melchior (2003) 215 CLR 1). In Harriton v Stephens (2006) 80 ALJR 791; [2006] HCA 15 and Waller v James; Waller v Hoolahan (2006) 80 ALJR 846; [2006] HCA 16 the High Court in a six-to-one decision (Kirby J dissenting) decided that no such claim could be made by a child when medical negligence in failing to order an in utero genetic test caused the child severe disability. In an era when almost all pregnancies will soon require patented fetal genetic tests as part of the professional standard of care, the High Court, by barring so-called "wrongful life" (better termed "wrongful suffering") claims, may have created a partial immunity from suit for their corporate manufacturers and the doctors who administer them. What lessons can be learnt from this case about how the Australian High Court is, or should be, approaching medical negligence cases and its role as guardian of the Australian common law?     

The use of error rates to predict and characterize the efficacy of presumptive field tests

From a forensic perspective, a presumptive test, one which indicates the presence or absence of a certain target material such as blood, is an invaluable tool. Among these tests, there are different specificities, sensitivities, and shelf lives. The accuracy of a test is an algebraic combination of the specificity and sensitivity of the test. Each test has limitations as given by its false positive and false negative rates. The aim of this study was to illustrate how the false positive and false negative rates are to be properly determined using a simulation study for the phenolphthalein test. New presumptive tests must be properly evaluated/validated through testing of commonly encountered household items and other potentially probative items usually found at crime scenes, however, the makeup of test sets must appropriately capture all error rates. In order to correctly use these results when the test is applied to an unknown sample recovered at a crime scene, the error rates cannot be applied directly to estimate whether or not the sample is actually the analyte of interest. In a validation study, the forensic scientist calculates the false positive rate as the p(Positive Reaction|Blood), whereas at the scene, the crime scene investigator wishes to determine the p(Blood|Positive Reaction). All crime scene investigators need to ensure that the conditional is not transposed when interpreting such results. Furthermore, this work provides a model for the assessment of a multiple test diagnostic system intended for investigators.     

The rapid determination of cocaine and other local anesthetics using field tests and chromatography

The application of field tests and chromatography to the detection of cocaine and some other local anesthetics that have been used to adulterate cocaine is described. Initial screening of samples by field tests, followed by concurrent TLC and GC, enables rapid identification of these compounds to be achieved. In particular, the use of flow-programmed GC shortens the time for analysis compared with conventional GC and requires negligible equilibration time between consecutive runs [12]. The method gives reliable quantitative data.     

新型荧光502粉末显现手印技术的改进研究

目的 对新型粉末状荧光502显现手印的方法进行进一步探索和完善,确保其高效便捷和科学准确.方法 将PolyCyano UV粉末加热至230℃使其升华,待该粉末在手印纹线上聚合附着后用长波紫外线或蓝光激发拍照,并与初步研究结果相比较.结果 大部分非渗透性光滑客体表面上的汗潜手印均有很好的显现效果.结论 该方法使显现流程更加高效便捷、显现时间短、无需二次染色增强、不破坏生物检材,适合推广使用.     

Interpapillary lines--the variable part of the human fingerprint.

The dermatoglyphic pattern of human palms and soles is individually unique and unchanging. Their prints show the course of the papillary ridges as papillary lines. Case reports and a few older studies of repeatedly taken fingerprints could, however, show that so-called interpapillary lines can develop between the papillary lines. The questions of this study were: How often do interpapillary lines occur? Can the differences between papillary and interpapillary ridges be quantified? Five-hundred and two ink prints of the palms and fingers from the archive of the Bochum Police Department were examined retrospectively. In 121 volunteers, the appearance of interpapillary lines was examined prospectively. From the later collective, the fingerprints of 13 people with interpapillary lines and nine people without were examined further by taking two silicon prints and measuring them with laser profilometry In 215 of the 502 ink prints (42.8%) interpapillary lines could be demonstrated. In those subjects younger than 20 years they were less frequently observed (34.1%) than in those above the age of 20 (51.8%). In all cases using laser profilometry the interpapillary lines could be related to a corresponding interpapillary ridge. The interpapillary ridge heights were 24.9 +/- 10.0 microm, significantly lower than the papillary ridges, which measured 59.0 +/- 19.2 microm. Interpapillary ridge widths were with 194.8 +/- 65.1 microm significantly narrower as compared to 435.5 +/- 57.4 microm in the papillary ridge. Those papillary ridges, between which interpapillary ridges were found, were significantly further apart from each other (610.5 +/- 78.9 microm) than those without interpapillary ridges (484.9 +/- 70.6 microm). During the course of a lifetime new ridges between the regular papillary ridges can develop or manifest. The fact that interpapillary lines are more frequently found on the right hands in men and those with increasing age is consistent with the theory that they correspond to degenerative changes and with sensitivity of touch.