海量数据取证方法的探讨

目的对当前我国电子物证检验中提取到的海量数据信息的取证难题进行探讨。方法对数据文件中海量数据信息的特点及其传统取证方法进行分析研究。结果提出开发专用工具软件进行海量数据文件的提取。结论利用专用提取工具软件可以对常见数据文件中有规律性的数据内容进行读取、计算、查重和汇总,使海量涉案数据文件的检验从传统的人工方式转变为计算机的自动处理。     

法医现场勘查学初析

法医现场勘查是公安法医检案的一个组成部分,与痕迹现场勘查各有侧重。本文通过室内、野外、运动空间三类现场初步分析了法医现场勘查的要点。     

Toxicological investigation of liquid petroleum gas explosion: human model for propane/ethyl mercaptan exposures

Four individuals died as the result of a propane explosion. As with many propane explosions, the question was raised as to the adequacy of the product's odorization after the autopsy studies had been conducted. In most cases, this question leads to litigation. Ethyl mercaptan is a widely used odorant for propane and was used in this instance. Three of the four victims had blood available at autopsy for study. Quantitative analyses of the victims' blood, obtained during autopsy, were performed using gas chromatography/mass spectrometry, without subjecting the samples to hydrolysis. These analyses determined the relative amounts of propane and ethyl mercaptan in the blood to be 90, 63, and 175 mL/m3 headspace, and 0.36, 0.34, and 0.77 microgram/L blood, respectively. Since mercaptans have been reported in human blood as products of metabolism, modeling studies were conducted to establish the validity of the autopsy data and to develop an autopsy toxicology protocol for investigating explosion deaths. When subjects were not exposed to an atmosphere containing ethyl mercaptan, dimethylsulfide was the only mercaptan detectable in their blood without severe hydrolysis prior to analysis. Metabolic ethyl mercaptan is sufficiently bound to be undetectable by the methods used without hydrolysis. Human subjects were exposed to a flammable mixture of air and propane odorized with ethyl mercaptan. The analyses of the blood from these subjects produced results which were comparable with those for the explosion victims, establishing that the question of odorant adequacy can be addressed at the autopsy of propane explosion victims. It is extremely important that the pathologist and toxicologist investigating gas explosion deaths recognize the valuable evidence existing in the victim's blood.     

AIDS and infection control in forensic investigation

Infection control in the workplace is becoming an increasingly important issue, not only for health care workers, but also for any workers who could potentially be exposed to infectious material. We discuss the nature, modes of transmission, and infectivity of important infectious agents likely to be encountered in the course of forensic investigations. We provide principles and guidelines for appropriate procedures and practices to be followed in a program of infection control.     

The analysis of forensic samples using laser micro-pyrolysis gas chromatography mass spectrometry

Laser micropyrolysis gas chromatography-mass spectrometry is used for the analysis of paint, photocopier toner, and synthetic fiber materials to test the forensic potential of this emerging technology. It uses a laser microprobe to selectively target very small parts of the materials for GC-MS analysis. Whereas the paint and the toner samples were amenable to direct laser pyrolysis, the synthetic fibers proved transparent to the 1064 nm laser radiation. The difficulty with the fibers demonstrates that a specific laser wavelength may not be appropriate for all types of materials. Nevertheless, the fibers were able to be indirectly pyrolyzed by impregnation in a strongly absorbing graphite matrix. A vast array of hydrocarbon pyrolysates was detected from the different materials studied. Unique product distributions were detected from each sample and in sufficient detail to facilitate individual molecular characterization (i.e., molecular fingerprinting). The integrity of the laser data were confirmed by comparison to data obtained from the same samples by the more conventional pyroprobe pyrolysis GC-MS method. The high spatial resolution and selectivity of the laser method may be advantageous for specific forensic applications, however, further work may be required to improve the reproducibility of the data.     

鉴侦分离机制研究

我国刑事司法实践中存在的"鉴侦合一"现象,违背了鉴定活动与司法活动分离的法定原则和科学鉴定的客观公正立场.鉴侦分离机制要求司法机关内部鉴定机构独立化,鉴定活动与司法活动的界限应予以明确,还应通过将侦查与鉴定工作任务、组织机构进行分离,纠正刑事诉讼法关于"鉴定"的立法表列来区分鉴定与鉴别的关系,进而构建鉴侦分离的机制.     

Soil sample metagenome NGS data management for forensic investigation

Soil analysis is a valuable resource in forensic investigation. Classical forensic soil analysis involves examination of its physical characteristics and chemical composition, such as soil type, colour, particle size, shape, pH, elemental, mineral and organic content. However the limited variability of these parameters is not always allowing adequate discrimination between soil samples. As soil supports extreme diversity of microorganisms and eukaryotic communities, microbiological approaches have been proposed. Several molecular approaches for microbial DNA profiling are available; however there is a lack of published data of implementation of the next generation sequencing (NGS) approaches for forensic soil analysis.The aim of the current study was elaboration of criteria for soil metagenome data management and database searching. We used our previously sequenced collection of 11 samples collected from different environments (forests, fields, grasslands, urban park) with different flora. The single sample collection includes 9 soil samples per one sampling area (30 m × 30 m) spaced by 15 m. In the current study we concentrated mainly on 18S rRNA gene V2-V3 region for fungi however SSU rRNA region for arbuscular mycorrhizal (AMF) fungi and V2-V3 hypervariable region of 16S rRNA gene for bacterial communities were taken into account. The sequencing was performed by Roche/454 platform. For data analysis OTU based approach on mothur software and NCBI BLASTN search were used. NCBI BLASTN analysis revealed altogether 2983 AMF matches and 8997 18S matches as well as 25477 OTUs (16S) were determined. Several data filtration approaches were used for data management. We found that 18S marker results could be used to create and run a filtered database that is computationally much more efficient and flexible. Our results have broad impact; however more samples have to be analysed, additional studies performed and cooperation between soil scientists and forensic scientists is required to be able to implement these novel techniques into the routine forensic practice.     

A forensic image processing environment for investigation of surveillance video

We present an image processing software suite, based on the Matlab environment, specifically designed to be used as a forensic tool by law enforcement laboratories in the analysis of crime scene videos and images. Our aim is to overcome some drawbacks which normally appear when using standard image processing tools for this application, i.e. mainly the lack of full control and documentation on the operations which have been performed on the images, and the absence of new, more sophisticated algorithms which can provide improved performances and "make the difference" in critical cases.     

掌骨骨折损伤程度及法医学鉴定

探讨掌骨骨折的致伤特点及活体损伤程度的法医学鉴定。对 5 2例掌骨骨折的案例资料按不同掌骨及损伤类型进行分析。第 1～ 5掌骨分别对于掌骨头、掌骨颈、掌骨干、掌骨基底部的骨折发生率和致伤机理各有不同 ,直接暴力所致第 2掌骨头、间接暴力所致第 5掌骨颈、第 3和 4掌骨干及第 1掌骨基底部等部位的骨折最常见。分析结果表明 ,掌骨骨折损伤程度不同 ,其损伤机理不同 ,各有其特点     

The relationship between serial sexual murder and autoerotic asphyxiation

This case series documents and examines the association between autoerotic asphyxiation, sadomasochism, and serial sexual murderers. Autoerotic asphyxiation, along with other paraphilias found in this population, is reviewed. Five cases of serial sexual killers who engaged in autoerotic asphyxiation were identified worldwide: four from the United States and one from Russia. Case reports for each are provided. All (100%) were found to have sexual sadism in addition to autoerotic asphyxiation. Furthermore, two (40%) had bondage fetishism, and two (40%) had transvestic fetishism, consistent with these paraphilias co-occurring in those with autoerotic asphyxiation. Overall the group averaged 4.0 lifetime paraphilias. Some possible relationships were observed between the offenders' paraphilic orientation and their modus operandi, e.g., all of these serial killers strangled victims-suggesting an association between their sadistic and asphyxiative paraphilic interests. The overlap of seemingly polar opposite paraphilias in this sample--sexual sadism and autoerotic asphyxiation--is explored from a historical and clinical perspective. Multiple commonalities shared between these five offenders and serial sexual murderers in general are addressed. A primary limitation of this study is its small sample size and empirical basis; the results may not be generalizable beyond the sample. The findings from this study support the supposition that crime scene behaviors often reflect paraphilic disturbances in those who commit serial sexual homicides.     

河南省刑事案件司法精神病学鉴定案例的随访研究

目的研究司法精神病学鉴定后各方对结论及处理的看法及社会影响等随访因素。方法作者通过通信函调、电话随访和登门拜访等三种方法,用自编调查表对208例鉴定案例分别向委托机关、被鉴定人本人或家属、受害人本人或家属进行随访。结果被鉴定人受教育年限平均为4.84年,以30岁左右已婚男性农民居多。暴力犯罪(129例占83.77%)远较非暴力犯罪(25例占16.23%)为多,前者又尤以杀人(44例占28.57%)为最常见。本资料再鉴定率为2.93%。被鉴定人及其家属对34例无责任能力的处理意见认为恰当的占76.47%,对判为无罪释放的28例,认为处理恰当的占71.43%,认为不恰当的占10.7%。对就医者几乎全都满意,对判刑或关押的认为恰当与不恰当者各占43.18%。受害人目前现状为死亡7例,残废10例,恢复健康10例。被鉴定人及其家属的意见与司法机关认为案件引起的社会影响似乎无关。被司法机关无罪释放的41例(26.62%)被鉴定人中,再杀人2例(4.87%),放火2例(4.87%),盗窃2例(4.87%),回归社会后有破坏行为但尚未构成犯罪者3例(7.31%)。结论建议政府有关部门尽快建立违法犯罪精神病人的监管和医疗机构。     

犯罪现场勘验中法医的职业安全

因鉴定体制特点,国内法医除鉴定工作外,还需进行犯罪现场勘验工作。在此过程中,可能面对很多风险,受伤和中毒等事件时有发生。然而,国内对现场勘验工作的防护只有少量规定,且内容不够详尽。本文对法医在现场勘验中的职业健康现状进行了分析,并将危害因素分为人、物、环境和管理四类进行论述。最后,从组织和技术两方面提出了具体防范措施。     

The analysis of illicit methaqualone containing preparations by gas chromatography-mass spectrometry for forensic purposes

A validated gas chromatographic-mass spectrometric method for quantitative analysis of methaqualone (MTQ) in illicit preparations is reported. The method proved to have a coefficient of variation of below 5%. Four batches of seized tablets, two pairs with similar imprints, were analyzed. It was found that the average MTQ concentration in all four batches of tablets differed significantly (p = 0.01) rendering it impossible to conclude that, on the basis of MTQ concentration alone, the batches with a similar logo originated from the same manufacturer or manufacturing batch. Conversely, it can be said that in this case, the four batches originated from either different clandestine laboratories or manufacturing batches.     

The role of the forensic pathologist in the investigation of fatal traffic accidents — The Finnish system

In Finland about one-half of the fatal traffic accidents are investigated by special Boards of Inquiry. The cumulating data serves multidisciplinary sciences, juridical and insurance purposes and legislation. The participating physicians benefit from the systematic work of the Boards in many ways. As an example of the results a list of causes of accidents is shown.     

An empirical investigation of written risk communication in forensic psychiatric evaluations

Abstract

There has been an increased interest in approaches for improving violence risk assessment, but less so how to communicate risk assessment results. We studied the written risk communication of 142 cases of forensic psychiatric evaluations in Sweden. The results suggested that risk for criminal recidivism was communicated in the vast majority of the cases (122 out of 142), but that risk was primarily communicated when the risk was perceived to be high. A six-item protocol to assess the content of the risk communication suggested that the communication was well elaborated in 21/122 of the cases, moderately elaborated in 53/122, poorly or very poorly elaborated in 43/122, and non-elaborated in 5/122 of the cases. Level of elaboration was only vaguely related to sociodemographic characteristics pertaining to the assessed (sex, age, citizenship) and the type of crime committed, but highly correlated to clinical diagnoses (DSM-IV) as well as contextual factors of the evaluation (which professional group and which clinic the assessment was performed).     

全二维气相色谱在刑事技术中的应用

综述了近年来发展起来的全二维气相色谱(GCхGC)技术正交分离系统原理及其特点以及在刑事技术中应用的发展前景。     

Three cases of sudden death due to butane or propane gas inhalation: analysis of tissues for gas components

We report three cases of sudden death due to inhalation of portable cooking stove fuel (case 1), cigarette lighter fuel (case 2), and liquefied petroleum gas (LPG) (case 3). Specimens of blood, urine, stomach contents, brain, heart, lung, liver, kidney, and fat were collected and analyzed for propylene, propane, isobutane, and n-butane by headspace gas chromatography. n-Butane was the major substance among the volatiles found in the tissues of cases 1 and 2, and propane was the major substance in case 3. A combination of the autopsy findings and the gas analysis results revealed that the cause of death was ventricular fibrillation induced by hard muscle exercise after gas inhalation in cases 1 and 2, and that the cause of death in case 3 might be hypoxia. It is possible that the victim in case 3 was under anesthetic toxicity of accumulated isobutane which is a minor component of liquefied petroleum gas.     

必须重视法医的命案现场勘验

命案现场勘验是法医的一项重要工作任务。但近几年没有得到足够的重视，甚至有的认为法医就是检验尸体，现场勘验可有可无，从而导致临案法医的作用被弱化和检案水平得不到提高。笔者就此结合案例进行相关探讨。