Simulative explosion is usable for restoring the course of involving event and reconstructing the relevant case scene. Hence, three choices of LS-PrePost-based simulative modeling were here tried about explosion with spherical charging: the keyword *LOAD_BLAST-guided, the SPH-directed and the keyword *INITIAL_VOLUME_FRACTION_GEOMETRY- led, thus having their advantages and disadvantages analyzed along with the applicable scenarios. All the simulations were conducted under the optimal load of 1 kg TNT charged into three different shapes so that the generated blast air-shock waves (represented with peak overpressure) were able to unfold their variations. The finite element software LS-PrePost was utilized to put into a verified finite-element model for the explosion simulation to carry out, with every simulation only changing the shape parameter of charging. The ANSYS\LS-DYNA was the solver to respond the discrepant ways of spherical, columnar and square charging in turn, having obtained the peak overpressure at diverse scaling distances, acquired some representative simulation data and delivered a statistical chart to compare the differences between every group of peak overpressure data. It was shown that there was a closer peak overpressure generated from the columnar charging and the spherical with the scaling distance less than or equal to 1.0 m·kg^-1/3, while that from the square charging and the spherical tending to a bigger difference. If the scaling distance was increasing, the ratio of peak overpressures almost kept stable from the columnar charging against the spherical, while that from the square charging against the spherical revealing gradually increasing and changing a lot. Evidently, shape-different charging does impact the generated shock-wave peak overpressure, deserving of no ignoring. Therefore, when investigating the charging with an actual explosive case and the consequent destroying effect, the explosion simulation should be carried out with the charging shape as close to the actual cases as possible. For exploration about the problems approaching to an explosion simulation, it is also necessary to choose the appropriate modeling way and charging setup so as to ensure the accuracy and reliability of the analysis and results.

牟××,男,24岁,未婚。曾因流氓罪强劳2年,1986年4月获释。同年8月连续强奸3人、杀死2人,致伤1人。牟在被追捕中欲强奸一青年妇女未成而将其砍死,接着又奸污了一名63岁的老人。后在追捕中被击伤。死后5小时尸检发现死者阴茎仍处在勃起状态。

Victimology in homicide crime scene analysis, the serial treatise published along with every issuance of the journal recently, has already been read twice by the public. In the first two pieces of the serial, an introduction to the discipline and the relationship between victims’ identity and crime scenes were illustrated and discussed. This paper, the third one of the serial treatise, places its emphasis on the life background of victims, aiming at calling forensic investigators’ attention to this aspect that sometimes is neglected in practice but can play key effects in solving relevant crimes. To address the matter, four portions are expounded here by the victims’ inclination of emotion to begin with, which takes as examples of two cases where all the victims died from thuggee with the decedent in one case through his willingness to conduct homosexuality and two men in the other one involved in the murderer’s pretence to answer their marriage-seeking. For the role of relationship between family members in homicidal crime, the explanation is assisted with a case where a wife killed her husband because of the final inability to endure the chronic maltreatment of the dead. Certain interpersonal relationships are at times implicated in murder case, and an auxiliary instance was shown with five people dead as a result of the killer’s hatred against his five work-mates’ repetitious mocking and bullying. Occasionally the culprits take advantage of victims’ religious belief and superstition to commit crime. The fourth portion is concerned with this point, highlighting it in a case that three female pilgrims were lured to the remote places to be slain when the murderers, conjecturing to achieve or consolidate their illusional noblest status of “emperor” or “empress” by way of killing people, found the dead bringing incense to get benediction from praying to some supernatural existence. Besides, many other general essentials linking to peruse the crime scenes are mentioned as well in this paper.

Presently, such an increasing demand emerges for the identification of complex genetic relationships in forensic practice that requires the combination of a variety of genetic markers, e.g., STRs, X/Y specific indicators, SNPs and mitochondrial DNA. Next generation sequencing (NGS) approach is able to integrate multiple genetic markers into one detection system, excelling the traditional capillary electrophoresis (CE) technology in overcoming the cumbersome operational procedures and experimental handling. Here, a typing panel, designated as DNATyper^TMNGSPanel v1.0, was developed with enclosure of human 29 autosomal STRs, 36 Y-STRs, 32 X-STRs, 71 Y-SNPs and the whole genome of mtDNA. Its validation was implemented under the guidelines of the Scientific Working Group on DNA Analysis Methods (SWGDAM), having evaluated the items of repeatability, accuracy, consistency, sensitivity, mixture and species specificity. For the developed DNATyper^TMNGSPanel v1.0, a consistency of 99.72% was shown to the detection with CE, plus the complete identical results coming true between the genic loci shared with it and the Forenseq™ DNA Signature Prep Kit. No allelic loss occurred to the DNA template of 0.5 to 10 ng, yet the respective 2 and 9 loci being lost with the 0.25 ng and 0.125 ng of template. Regarding to the mixture of male and female substances, the mixed ratio of 2׃1 had the the female’s begun to appear allelic loss, contrasting that the mixed ratios of 9׃1, 4׃1, 2׃1 and 1׃1 brought the positive detections to 54.72%, 81.13%, 98.11% and 100%; and the mixed ratio of 1׃4 made the male’s happen to allelic loss, opposite the mixed ratios of 1׃1, 1׃2, 1׃4 and 1׃9 rendering the positive detections to 100%, 100%, 90.24% and 82.93%. The test of species specificity proved that the developed DNATyper^TMNGSPanel v1.0 hardly amplified the DNA from pig, cattle, mouse, either the cynomolgus monkey or the rhesus one. In conclusion, the developed DNATyper^TMNGSPanel v1.0 is of high detection throughput, high sensitivity and stability, accurate and repeatable typing and good ability for mixed sample to detect. Also, it can deliver the genetic information related to paternity and maternity at the same time in just a single run of test with any common biological samples, hence eligible for boosting the capability of individual identification and efficiency of consanguinity determination.

As soon as ChatGPT came out, it attracted widespread attention. This article takes ChatGPT as an example, briefly describes the use, characteristics and advantages of large language models, and analyzes the current controversies, ethical dilemmas and information security risks. This paper focuses on the analysis of the possible applications of large language models in crimes, and discusses the use of ChatGPT to assist in the acquisition of criminal skills, the implementation of cybercrimes, phishing attacks, and the dissemination of false information. This paper also explores the use of ChatGPT at the law enforcement fields, including serving crime fighting, crime prevention, law enforcement decision-making, and law enforcement capacity building. This paper believes that law enforcement agencies should keep an open attitude, pay close attention to the impact of the application of artificial intelligence technology on crime, represented by ChatGPT. Law enforcement agencies should strengthen research and deal with ChatGPT from both aspects of “positive” and “negative” attitude, applying new technologies to help with law enforcement activities and improve efficiency.

笔者在尸检中见一男性尸体阴茎呈勃起状态,并通过对阴茎表面及会阴部附着物的检验结果,认定这是一起奸情杀人案。现报告如下: 1979年冬某日,接群众报告,在一废弃的仓库内发现一具男尸。尸体用草覆盖,一侧地面上有拖痕及自行车印痕,尸体肢端被冻僵。经调查,死者系农民,62岁,鳏居多年,体质健壮。于死后约14时尸检见头颅变形,颅盖广泛性骨折及多发性头皮裂创,脑组织挫碎外溢。同时见其阴茎呈半勃起状态,在阴茎表面及会阴部皮肤上附有大量分泌物。经镜检见分泌物的主要有形成分为大量的无核及有核鳞状上皮细胞和数个燕尾状上皮细胞,未查见精子。

This article tries to summarize the recent advances of fingerprint technology and demonstrates ten possible developing directions in the future: 1. more sensitive reagents; 2. fingerprit detection on surfaces difficult to handle; 3. time-resolve (TR) and phase-resolve (PR) technology; 4. chemical imaging technology; 5. fingerprit detection on the exhibits polluted by bio-, chem- and/or nuclear-hazardousness materials; 6. immune and aptamer technology; 7. forensic intelligence from fingerprit detection; 8. the use of 3rd level characteristics in fingerprint identification; 9. age estimation for fingerprits; 10. more powerful Automatic Fingerprint Identification System (AFIS).

At present, most cases of guns misfire are caused by the old and loose gun parts and the failure of safety parts, which leads to guns misfire in the process of disassembly, wiping, touching and bumping. This paper introduces a case in which the naked firing trigger of the altered nail gun was hit by wrappage, causing death. Combining with the opinions of on-site investigation and autopsy, a simulation experiment was carried out to explore the formation mode of the shooting wound of the deceased and whether the gun misfire could be caused by hit. The whole process of gun misfire was restored by experiment, and the rules and characteristics of gun misfire were analyzed and discussed, which could provide reference for similar cases.

New synthetic opioids are on the growing list of illicit drugs and pose a serious threat to human health. Some examples of NSOs include AP 237, piperidine, bromomorphine and a variety of 2-benzyl benzimidazole opiates. 2-benzyl benzimidazole opioids, also known as “Nitazenes”, many of which are regulated by the United Nations Commission on Narcotic Drugs, have become internationally prevalent in recent years. Metonitazene is an emerging potent synthetic opioid that first appeared in the recreational drug supply in mid-2020 and began to surge by the end of the decade, raising increasing public health concerns. In this study, we presented a method for the identification of a novel synthetic opioid metonitazene seized for the first time in China by gas chromatography-mass spectrometry (GC-MS) and ultra-high performance liquid chromatography-quadrupole/electrostatic field Orbitrap-MS (UPLC-Q- Exactive Orbitrap-MS). The unknown samples were extracted by methanol, and the supernatants were analyzed by GC-MS and UPLC-Q-Exactive Orbitrap-MS respectively. Isotonitazene was analyzed as a contrast. By GC-MS detection, the main characteristic ion peaks of the mass spectral fragments of unknown component with retention time of 15.167 min were m/z 86.1 (base peak), 58.05, 121.1, 205.05, 236.05 and 248.1. UPLC-Q-Exactive Orbitrap-MS detection showed that the excimer ion peak of unknown component with retention time of 7.35 min was m/z 383.207 7. The main ions of secondary mass spectrum were m/z 310.118 2, 264.125 2, 121.064 9, 100.112 1 and 72.080 8. Due to the lack of reference substance, the target was identified as metonitazene by retrieval of SWGDRUG and Cayman database, comparison of information in reported literatures and analysis of high-resolution mass spectrometry data. The method is simple, rapid and has good application prospect. It can be used in real case detection.

At present, artificial intelligence (AI) is constantly innovating and developing, especially in machine learning and neural network. Its achievements have been widely applied into various industries including forensic science. The basic forensic research assisted by AI covers the forensic disciplines among pathology, biology, clinics, toxicology, anthropology, entomology and other fields, thereby having provided new ideas and methods for solving traditional forensic problems, promoted great development of various forensic subjects meanwhile bringing forward tremendous forensic application progress. With a brief general introduction of AI to begin, this paper mainly summarizes the research achievements of AI from forensic DNA typing, postmortem interval inference, individual characteristic depiction, age and/or sex judgment, screening and peak interpretation of toxic target compounds to imageological and pathological diagnosis about tissue sections. Moreover, discussions were made of the problems to be solved urgently and the troubles coming from development.

As the fourth portion of the serial treatise of victimology in homicide crime scene analysis, this paper relates the homicidal crime scene analysis to victim’s body injury which can be classified into two major types, one is the trauma that the culprit intentionally enforces to exert against the victim, for example the injuries over being attacked, and another is the one caused by other reasons such as the tumbling and bruising during a crime. Here the emphasis places on the first-mentioned type because the body injury formed with purposive exertion has capacity of reflecting the conditions of the criminal’s physiology and psychology so that forensic physicians often use the traits of victim’s body injury to make judgments and decision to excavate the criminal motives and/or depict the offender. The common-discussed body injury is consisted as follows: 1. degree of damage, indicating not only the severeness to leave one victim’s life in danger but also the different injuring degrees among the dead in cases of multiple lives claimed; 2. injuries formed with special tools, those created with the shape-and-usage-specific tools which are not commonly used and seen, either; 3. intensified trauma, one that is further inflicted by the criminal to ensure death after killing the victim; 4. wound out of abreaction, like the intensified trauma, the additional damage enforced by the offender to discharge wrath following putting the victim to death; 5. coercion injuries, those of the non-lethal ones produced by the culprit to ask the victim to obey for certain purpose, usually taking place at the early stage of crime; 6. left-handed trauma, one that is engendered by the suspect who is a left-handed, and to define such kind of injury requires that the attacker and the attacked be unambiguous in their opposite positions.

Since its establishment in 2008, the Asian Forensic Sciences Network (AFSN) has become an important platform for the communication of forensic institutions in Asia, with its international influence gradually increasing. China was elected as the presidential nation of AFSN for the first time in September 2017, playing ever since its prominent role in this organization. This paper introduces the basic information about AFSN, its foreign liaisons, and the latest five annual meetings & symposia. With analyzing different participation of each involving country and reviewing China’s boarding into the organization, China is certainly continuous to participate in AFSN, exerting its significant leading functions through international cooperation in forensic science.

Fingermark is one of the most valuable physical evidence and generalized proof of identity for its characteristics of specialty and stability. Latent fingermark, the most common evidence, poses the most challenges when being examined to show contrast present yet non-sufficient between the mark and its support. Surface phenomena and environmental conditions play an important role in the choice of fingerprint detection techniques. In general, all surfaces bearing latent fingermarks can be divided into three types: porous, semi-porous and nonporous. Property of an unknown surface has to be considered before any attempt is made to develop latent fingermark. Preliminary test should be conducted on a similar surface before proceeding with any treatment of an evidential item. Along with the fingermark detection technology being improved, the process has been further optimized and its sensitivity and specificity being advanced. In this paper, the latest techniques and material used in different surfaces to enhance and record fingermarks are reviewed. A larger number of techniques are presented here and discussed according to surface properties from practical perspective. For example, optical detection, fingerprint powder, small-particle reagent (SPR), cyanoacrylate fuming and vacuum metal deposition (VMD) can be used to nonporous surface. Ninhydrin, physical developer (PD) can be used to porous surface, some miscellaneous techniques can be applied to a wide range of porous and nonporous surfaces, even for some challenging surfaces. Furthermore, some modern instrument analysis techniques can be used to enhance the visualization of latent fingermarks. Finally, we summarize the advance of research on the development of latent fingermarks, discuss the challenges facing the fingermarks examiners, and predict the future and perspective research of latent fingermarks development.

Synthetic cannabinoids are of hallucinogenic effect equivalent to or even stronger than that of cannabis, being listed under the first batch of new psychoactive substances controlled in China. There are many kinds of synthetic cannabinoids, among which MDMB-4en-PINACA and ADB-BUTINACA are recently the two ones of most active alkyl formyl indazole in the market. Such two synthetic cannabinoids have presumably not been reported about their metabolic researches in China. Thus, both the MDMB-4en-PINACA and ADB-BUTINACA were here probed into their metabolites from the blood and liver of rats. With 12 SD rats randomly divided into two equal groups: one for MDMB-4en-PINACA and the other for ADB-BUTINACA, each rat was fasted for 12 h and then intraperitoneally administered once by weight as per 1.0 mg/kg along with the two groups leaving one rat taken as the control that was not injected of drug yet executed just before administration. The remaining five rats in each group administered of drug were respectively killed at 5, 15, 30, 60 and 120 min after drug injection, having their blood and liver tissues received and successively analyzed into high performance liquid chromatography quadrupole time of flight mass spectrometry (HPLC-QTOF). The results showed that the experimental rats had MDMB-4en-PINACA metabolized into corresponding metabolites through double bond oxidative carboxylation, ester hydrolysis, 4-depentenylation and hydroxylation, with ADB-BUTINACA being metabolized through hydrolysis, 4-dealkylation, 4-butyl hydroxylation and hydroxylation. According to the response intensity of components in blood and liver tissue of rat, MDMB-4en-PINACA mainly converted into its metabolites from pentenyl oxidative hydroxylation (No. M6), pentenyl oxidative carboxylation (No. M7), methyl butyrate hydrolysis (No. M2) and further hydroxylation (No. M3/M4/M5) and dealkylation (No. M1), demonstrating its metabolic markers as M1 and M2. ADB-BUTINACA mainly turned into its metabolites from debutylation (No. A1), formamide hydrolysis (No. A2), butyl carboxylation (No. A3) and butyl hydroxylation (No. A4), with its metabolic markers being as A1 and A2.

The 13th Five-Year Plan is an important one among the strategic opportunities for the development of forensic science. With summarization of the status quo of forensic science, the goal of forensic science was here put forward in the new era through strengthening the overall design of the essential elements across whole chain, focusing on solving common problems and promoting the all-inclusive elevation of total involved disciplines. Therefore, in the 13th Five-Year Plan, forensic science should especially pay attention on researches about advancing basic theories, suspects’ characterization depiction, evidence analysis and tracing provenance as well as the quality assurance, in order to achieve breakthroughs from theory and technology and promotion of identification quality. Finally, the trend was looked into the intellectualization, standardization and industrialization for the future development of forensic science.

Damaged glass, out of shooting (or hitting), frequently occurs in crime scene. Although the priority is to ascertain the shooting device’s type when such scene is encountered, yet it is difficult to accurately confirm the weapon used because of the prevailing presence of many sorts of shooting devices and bullets (or pellets) to result in very rare verification from actual cases. Therefore, the judgment is always relied on the experience of experts. In this paper, mark evidence on flat glass was made and investigated from several types of weapon including slingshot, crossbow, air gun, ball gun and pistol. Simulated shooting test was targeted at flat glass (thick of 3.5-5.0 mm) with the above weapons under different conditions, producing 191 pieces of cracked glass samples. The patterns on the cracked glass, generated by different weapons and projectiles, were carefully examined and compared. Experimental data show that the degree of glass damaging is stable when both the velocity of the projectile and the used pellet matching to some weapon are relatively fixed. According to the extent of damage, the patterns of marks on glass are divided into five categories, with their majority showing combination of two and more categories. Based on the probability of occurrence, category combination and size of the marks, the characteristic of the marks is concluded. Projectiles of stone, steel-ball and gun bullet can be distinguished by the shape of the holes produced on the cracked glass. The caliber of pellet by slingshot, crossbow or ball gun can be judged by the size of the crack. The radial crack by air gun especially tends towards bending. The types of the applied weapons can be deduced by the pattern of the marks. The influential factors on stability of the mark patterns, and the projectile’s track can be ignored but the flat glass’ characters, such as the size and thickness, must be taken into analyzing the diameter of bullet (or pellet) hole. The discovery here may provide reference for more refined inquisition about mark evidence on the damaged flat glass so as to determine the shooting device quick and accurately.

Among digital evidence examination, Android phones present high profile. Usually, examiners try to get root authority (highest in the system) to get physical dump-images from the Android phone so that the data can be fully extracted and recovered as many as possible. However, the constant updating of Android system make it even more difficult for the root authority to get, leading to high risk of damaging the data. Thus, it is getting imperative to acquire the physical dump-images from Android phones with no requirement of root warrant in digital forensics. In fact, there are available choices of third-party recovery, dedicated communication interface or Android special boot mode and others so as to effectively improve the success rate of dump-image acquisition from Android mobile phones.

As the sixth (the final) portion of the serial treatise of victimology in homicide crime scene analysis, this paper relates the homicide crime scene analysis to victim’s life state. The life state of victim can be classified into four major types relating to time and space, dressing, work and rest, and body position, respectively. The time-and-space state refers to the time, location and position when the victim is attacked. The dressing state is the victim’s apparel when the crime occurs. The work-and-rest state is the living status when the victim is killed, usually being divided into three types of normal, rest and sleep. The body position refers to the victim’s physical condition during and after the attack. In this paper, the four aspects are analyzed and discussed with specific cases aiding. In practice, we might be able to analyze the relationship between the victim and the suspect, and the suspect’s identity according to the life state of the victim.

Objective To investigate the factors that affect the rifling to leave marks on airgun pellets so as to facilitate the gun identification through contrasting the ballistic evidence from marks on airgun pellets. Methods Five rifling airguns were selected for test. Samples of ballistic evidence were obtained by use of different airgun pellets, with changing the rifling either at the muzzle or breech. The obtained pellet samples were examined under microscope to observe and analyze the factors that affect the left rifling marks. Results The rifling marks left on airgun pellets can be affected by the kinds of pellet used, the changed rifling both at the muzzle or breech, with the most significant impact being from the rifling changing at the muzzle. Conclusion Upon examination, high attention should be paid to the marks left from the changed rifling either at the muzzle or breech, thus secure to make the original rifling marks found.

一九七五年三月十四日,台山县附城公社社员陈××(男,39岁)被其岳父陈炳夫用毒蛇杀死。死者是一九六八年由陈炳夫介绍与其女儿结婚的,婚后生活贫困,感情不和。一九七四年后,陈炳夫父女两人会多次向死者提出离婚,均遭死者拒绝,因此怀恨在心。

DNA identification plays an important role in criminal investigation. But when the evidential DNA does not match either a suspect’s STR profile or any other one’s in a criminal DNA database, and/or the mass DNA screening and family searching failed to give any information for tracing unknown forensic sample’s donors, cold cases would be even caused, leaving them to be waited for various periods of time (likely very long) to solve. Predicting human externally-visible characters (EVCs) of an unknown person is an emerging contrivance by which to provide investigative hints allowing to trace the suspect, who is not identifiable via conventional comparative DNA profiling. In recent years, the potential of constructing useful DNA-based facial portrait is of great interests in forensic studies. Facial morphology is a combination of many complex traits, highly heritable, because much of the total variation in facial features is genetically mediated. At the early-stage of the kind of researches, the knowledge of genetic variation on facial morphology has mainly arisen from studies of genetic abnormality such as non-syndromic cleft lip with/without cleft palate (NSCL/P), and from those of developmental mechanisms, including PAX3, FGF, GHR and many other signaling pathways. In these studies, facial characters were traditionally simplified by straight scalar measurements, e.g., nose-width or eye-distance, therefore having no differences from the measurements of height, BMI or pigmentations. However, facial morphology is such an extremely physical complexity that dimensionality reduction techniques, where each principal coordinate is treated as a scalar trait, can cause the statistical power decreased dramatically. Recent advances have produced novel methods for fully automatic 3D facial image mapping and crude models of facial structure constructed by SNPs variants analysis. The non-rigid registration method or spatially dense quasi-landmarker was applied for fully automatic 3D facial image mapping and aligned faces via high-density pixel points. Based on these methods and joint modeling of sex, ethnicity and genotype, the independent effects of particular alleles on facial features will be uncovered and a 3D facial prediction model could be built. In the future, such developments will lead to a more detailed description of an unknown person’s appearance from genetic variations, very likely to expedite police investigations by providing more scientific information of forensic evidence.

近10年来,某县发生了10例精神病杀人案,凶手经精神病院鉴定为突发性、间歇性精神分裂症患者。10例精神病杀人案中死20人,伤6人。笔者试图对这些案例所收集的资料作一分析,探讨精神病患者杀人与一般凶杀案在作案特点上的区别。 1 一般资料 1.1 性别、年龄、职业、文化程度与作案的关系 10例精神病杀人案的精神病患者均为男性,21～30岁4例(40％);31～40岁4例(40％),41～50岁2例(20％)。

N-isopropyl-benzylamine is very similar in appearance and physical properties to its structural isomer, methamphetamine. Discovered from the increasing cases, N-isopropyl-benzylamine can be used as not only an attenuant of “ice” methamphetamine but also one substance of trafficking and smoking. GC/MS methods were here established to test the N-isopropyl-benzylamine in vitro and urine respectively, together with the optimization of sample extraction so that both N-isopropylbenzylamine and methamphetamine are capable of effectively detecting under the same experimental conditions. Besides, an ascertainment was made on N-isopropyl-benzylamine of its concentration boundary beyond which the methamphetamine test kit (colloidal gold) will be false positive from the cross reaction of N-isopropyl-benzylamine. The methods are very simple, accurate and reliable, time-saving, meeting the needs for the police to identify N-isopropyl-benzylamine.

Depiction of individual’s EVCs (externally visible characteristics) based on DNA analysis is gradually becoming a forensic research hotspot because it can provide effective leads to police investigation when conventional DNA STR data do not match either known individuals or any criminal DNA database. Compared with the other morphologic features, human facial morphology is more conservative, less affected by environmental factors. Moreover, the combination of gene analysis and image technology has greatly promoted the research on facial morphological inference. In this paper, DNA facial prediction technique has ever been launched in forensic genetics for the first time. Through selection of 350 facial morphology-related SNPs analyzed from sequencing 24 Chinese males (18 Uygur and 6 Han), the relevant SNP phenotypes were obtained so that a model of facial morphologic prediction was built up based on such one of the previously-developed. By evaluation of the similarity between the genetic predicting faces and the real ones to show the model’s accuracy, some problems of the current technique were discussed together with the further researches that will be inevitably carried out in the future.

正确判定现场手印遗留的时间和新鲜程度,是一项比较复杂而又必需研究解决的实际课题。现场手印按遗留的时间和条件可分为新鲜手印、陈旧手印和原有性手印。下面介绍一些鉴别的方法,供参考。一、新鲜手印系发案前后一天时间内遗留在各种物体上的手印(灰尘手印和立体手印例外)。在不吸水的光滑物体上,一般可用400目铝粉呈现。

Objective To explore the key points for identification of the death from carbon monoxide poisoning by charcoal-burning in a closed room. Methods Twenty cases were collected of death from carbon monoxide poisoning by charcoal-burning in a closed room during 2013-2015 in Wenzhou, Zhejiang. Statistical analysis was performed into the collected materials. Results The majority of the cases was identified as suicide despite occasional exceptions. Direct evidence might be taken from the letters or notes left by the decedents just before death, which were likely written on paper, electronic devices and personal social media. Conclusion The main features of suicide from carbon monoxide poisoning are the decedent’s self-determined disposal of the scene although they are the required yet not sufficient basis for the judgment of suicide.

他杀死亡案的检验是法医检验工作的重要内容,为了探索他杀案的一般规律,提高对他杀案的识别能力及防范能力,现将我县18年来检验的他杀死亡案例作如下统计分析.1 资料来源与方法本文资料来自本局法医室自1980年至1997年12月检验的他杀死亡案例,共140例,按照统一的标准和要求逐年逐例查阅填表,然后统计出死者的性别、年龄、发案时间、加害手段发案原因等项目,并与正常人口资料及自杀死亡案对此分析.

本文通过实验研究的方法,寻找出JW—20型小口径步枪射击弹壳上稳定的枪种痕迹特征。

The interpretation of fingerprint evidence depends on the judgments of fingerprint examiners. Basing on fingerprint identification methods, standards and working experience, fingerprint examiner conducts fingerprint analysis, comparison and finally gives expert opinion which is one of the legal forms of evidence.This study assessed the accuracy of different judgments made by fingerprint examiners following the analysis process. 106 agencies were invited to take 4-trail experiment for identification following analysis, comparison and evaluation process. We compared the examiner’s judgments against ground truth and used a net-work based fingerprint identification analysis platform to evaluate how fingerprint examiners document their analysis during the identification process. The experiment information of each agency was recorded during the fingerprint identification process and data was calculated by statistical software R for statistical analysis .The results showed that different examiners demonstrated different accuracy of judgments and different mechanisms to reach them. The results also showed that there is a strong relationship between minutiae selection reliability and minutiae quantity and fingerprint quality.

Objective To classify the characteristics of marks on cartridge cases shot from seven kinds of 9mm pistols (NP22, WaltherP38, Steyr GB, FN M1935, Browning BDA, QSZ92, Glock19) for identifying the kinds of involving pistols. Methods Twenty pieces of DAP92-type 9mm bullets were shot with each selected pistol, with the cartridge cases being separately collected, observed and recorded of the marks on them by stereoscopic microscope. The marks’ characteristics were perused against each kind of the involving gun. Results Every pistol left characteristic marks on the cartridge cases, e.g., the rectangle firing-pin marks from Glock19 Pistol, the ejector abdicating-groove marks by Steyr GB Pistol, the horseshoe-shape bolt recess marks and fan-shaped scraping marks from QSZ92 Pistol, thereby making shape/position-different marks formed on cartridge cases from the related gun’s ejector, together with some pistols also producing tongue-like marks and magazine-mouth marks on the shot cartridge cases. All of the characteristics of the marks above are important basis for the distinction between the kinds of the test guns. Conclusion The kind of the relevant gun can be likely identified through observation and analysis of the relating marks on the cartridge cases shot with the seven-kind pistols tested.