The long way from electronic traces to electronic evidence

Generally, traces of Internet communications established by a citizen's computer are routinely recorded on and dated by Internet servers in so‐called ‘log files’. As far as the correct dating of the electronic offence is crucial for the potential identification of the author, convincing traces need to be date‐ and time‐stamped by a Trusted Third Party (TTP). Such a time stamp does not give any assurance about the correctness of the data and dates collected, but only proves that the traffic data were in a given state at a given date and time. If the Internet Provider (IP) address appears to be one used by the company, it is foreseeable that the system administrator within the company will be able to identify the computer owning a particular IP address. In others cases, only law enforcement agencies, in the circumstances and the conditions required by the law, are entitled to identify, with the help of Internet Access Providers (IAPs), the communication line suspected to have been used beside a given IP address. Putting together the traces left at the IAP side and in the log files of the attacked server site may lead, in the best cases, to an identified communication terminal. Nevertheless, in many cases, this will not be a formal authentication of a wrongdoer.     

程序与法律形式化——兼论现代法律程序的特征与要素

许多诉讼法学者认为 ,与其把程序法与实体法当作“形式与内容”的关系 ,不如把它看成“手段与目的”的关系。其实 ,程序法与实体法的关系 ,既是手段与目的的关系 ,又是形式与内容的关系。这就是说 ,程序既具有工具性 ,又具有形式性。     

The traces of smokeless gunpowder

The experimental investigation resulted in detection of new specific and characteristic signs of smokeless powder. Additional tests for determination and differential diagnosis of smokeless powder variants were suggested.     

Efficiency evaluation of the LT-DNA traces analysis modifications

Analysis of genetic profiles obtained from low template DNA samples (LT DNA) can be challenging because of increased probability of stochastic amplification artifacts occurrence. According to the recommendations of international genetic societies the quality of the LT-DNA traces results can be improved by applying low copy number (LCN) methods. Another strategy which allows to obtain better results of the analysis of LT-DNA traces is replicate the amplification of the same DNA sample and create consensus, composite (virtual pool profile) or real pool profile. The aim of the research was to analyze and compare the efficiency of modifications used in the testing of LT-DNA samples. Obtained results indicate that implementation of these methods in laboratory practice may lead to improvement in the quality of reported data from LT-DNA traces in genetic analyzes conducted to assist the justice system.     

Biological traces after falling on the staircase

Presents the results of experimental studies of biological traces which adhered during simulation of a trauma on a staircase, making use of anthropometrically balanced mannequins and biomodels. Analyzes blood and dust traces on clothes and shows that their position on clothes depends on the presence of pre-acceleration.     

Morphologic identification of mummified tissue traces

Post mortem tissue samples from various human organs (skin, muscle, liver, kidney, brain) were stored at room temperature for a period of one year. During this time the samples were regularly histologically tested. Without any pretreatment of the samples a histological preparation and identification was no longer possible after only a few hours. By the use of a rehydration solution consisting of absolute ethanol (30 ml), aqua dest. (50 ml) and 0.2 M phosphate buffer pH 7.0 (20 ml) a reconstitution and identification was again possible. Further immunhistochemical examinations were also unaffected by the solution. The use of microwave stimulation allowed a reduction of the rehydration process from 24 hours to only 4 hours.     

Situating forensic traces in time

Situating events and traces in time is an essential problem in investigations. To date, among the typical questions issued in forensic science, time has generally been unexplored. The reason for this can be traced to the complexity of the overall problem, addressed by several scientists in very limited projects usually stimulated by a specific case. Considering that such issues are recurrent and transcending the treatment of each trace separately, the formalisation of a framework to address dating issues in criminal investigation is undeniably needed. Through an iterative process consisting of extracting recurrent aspects discovered from the study of problems encountered by practitioners and reported in the literature, common mechanisms were extracted and provide understanding of underlying factors encountered in forensic practise. Three complementary approaches are thus highlighted and described to formalise a preliminary framework that can be applied for the dating of traces, objects, persons and indirectly events.     

普通话亲属称谓形式化初探

汉语亲属称谓具有区分辈分、性别、同辈长幼、直系旁系和姻亲血亲等特点,据此可以对汉语亲属称谓作出形式化判断;核心称谓、基本称谓是构成汉语称谓系统的基础;从属性亲属称谓所指的年龄、辈分由相应的核心称谓和基本称谓决定;除性别服从尾标记外,用附加法构成亲属 称谓,如果核心语素与附加成分包含相同义素,取附加成分义素,亲属称谓从右省略的现象也与之相互印证。     

Optimization of the collection and analysis of touch DNA traces

The aim of this work was to optimize a strategy for detection, collection, and analysis of touch DNA traces. 4N6FLOWSwabs™ and cotton swabs were compared by collecting touch DNA traces from glass slides and gun shell casings. Shed cells were visualized using Diamond™ nucleic acid dye and a digital fluorescent microscope. Different collection and extraction methods were tested. Collected samples were amplified with the AmpFlSTR® NGMSElect™ kit and the Precision ID mtDNA Whole Genome Panel.     

Isoenzyme determinations as aids in the identification of biological traces

The findings are described that were determined after a fatal traffic accident. By means of blood and isoenzyme typing, a piece of tissue adhering to the bottom of a car was ascribed to the victim.     

Detection of saliva traces using test strips

The test strip Rapignost-Amylase (Behring) for the rapid determination of alpha-amylase in the urine is also suitable for the determination of salivary amylase in stains stored up to 6 weeks at room temperature. The stains are extracted with physiological saline (extraction time 30 min), then the application zone of the strip is wetted with the extract. Positive amylase-reaction is recognised as a reddish-violet colouration of the reaction zone. Biological stains with low amylase concentrations (urine semen, vaginal secretion, mucus) react amylase negative. The method is uncomplicated and can be completed within 30 min. The test strips are easily available and stable during storage. Therefore the determination of saliva with test strips should be preferred to the clinical methods if the storage times of the stain are not longer than 4-6 weeks. It is a suitable procedure to determine salivary stains for use in forensic biology.     

Practical value of LDH-X determination for the detection of sperm traces

The examination of 38 stains collected in sexual offences provided spermatozoa-positive, LDH-X-negative results in 4 samples and spermatozoa-negative, LDH-X-positive results in 6 samples. The results suggest that besides the microscopic detection of spermatozoa the demonstration of LDH-X should be performed in medicolegal identification of seminal stains.     

论电子商务中的电子证据

本文对电子证据与传统证据进行了分析对比,指出了电子证据的特征,提出了对电子证据的可采纳性与证明力,以及在诉讼和仲裁中如何审查判断、使用电子证据等,发表了有见地的观点,对立法机关和司法实践都有一定的参考价值.     

Visualization of biological traces on evidence by ninhydrin

Because of possible contamination of samples with PCR inhibitors and to avoid the typing of mixed profiles the source material for forensic DNA investigations should be collected as directly and securely as possible from the evidence. This approach requires a detectability of the source material which is often not given. The procedure introduced here using selected cases enables visualization of DNA-containing materials on evidence and hence controlled analysis. For this purpose the specimen is treated with ninhydrin. A following dye reaction verifies the presence of biological material, which possibly contains DNA. An impact on subsequent STR-analysis was not observed.     

Reconstruction of sexual offences--forensic aspects of sperm traces

The investigation of sexual offences is a real challenge, as the injuries are often unspecific or faint and may sometimes be missing completely. Evidence recovery and analysis as well as the statements of the victims and suspects are therefore of vital importance. In both presented cases, the results of trace evidence analysis were basically consistent with a sexual assault, but the victims' statements regarding the course of events and the pattern of traces showed severe discrepancies.     

Recovery and detection of urea nitrate in traces

Urea nitrate (uronium nitrate, UN) is a powerful improvised explosive, frequently used by terrorists in the Israeli arena. It was also used in the first World Trade Center bombing in New York in February 1993. It is difficult to identify UN in postexplosion debris, because in the presence of water it readily decomposes to its original components, urea and nitric acid. A method for the recovery and detection of urea nitrate in traces is described. The residues are extracted with hot acetone, and the extract chromatographed on chromosorb G-HP. The eluent is analyzed by liquid chromatography mass spectrometry using atmospheric pressure chemical ionization (APCI). By applying this technique, we were able to identify urea nitrate in actual exhibits. It was found that UN can be also formed during the analytical procedure, by certain combinations of urea, nitrate ions, and a source of protons and, hence, the presence of the characteristic adduct ion does not necessarily indicate an "authentic" urea nitrate. Several solutions are suggested to overcome this ambiguity.     

Drug addiction in Poland and criminalistic traces

The authors describe the most popular drugs and their substitutes being used in Poland. The paper also presents the problem of developing and examining criminalistic traces in biological and some non-organic materials.     

Gm/Km determination in sperm traces

In the forensic laboratories of the Federal Republic of Germany and West-Berlin 23 different semen stains and in our own laboratory 20 semen stains were typed in the gm/km-system doing 125 and 61 (own) test respectively. Examination was carried out by means of the haemagglutination method, which has been used successfully in typing bloodstains. Our critical assessment based on earlier experiences with semen stains was now confirmed and statistically evaluated: typing was successful in about 35-50% of the tests, but besides false-negative results, there was also a considerable percentage (4-10%) of false-positive ones. Therefore for the present it seems best to exclude the gm/km-typing of secretion stains from forensic investigations in order to avoid false incriminations or exonerations of suspects.