Biometric electronic signatures as the new object of handwriting examination

Analyses of electronic biometric signatures constitute an innovation in forensics. The aim of the study described in this article was to determine whether it is possible to categorically confirm or exclude both the authenticity and the execution of handwritten biometric electronic signatures. Several-year-long research on various types of electronic signatures has made it possible to formulate categorical conclusions in this area. The article defines and determines the terminological scope of the biometric electronic signature concept within the widely understood electronic signatures. The analyses of biometric signatures were based on the graphical-comparative method commonly used in the traditional model of handwriting analysis. The only modification consisted in replacing the set of motoric features with biometric features, which turned out to be necessary for a categorical opinion on this matter. Study results described in the text allow for quantitative examination within analysis of manuscripts thus enabling issuing a categorical opinion. The biometric features of handwriting identified entirely by means of digital data ought to contribute to the elimination of any bias that might exist on the part of an expert.

Research on soils, stone products and rocks – selected cases of opinions issued by the Central Forensic Laboratory of the Police in Warsaw

Research on soils, stone products and rocks is part of a scientific discipline known as forensic geology. Among the police forensic laboratories, this type of studies are performed only at the Chemistry Department of the Central Forensic Laboratory of the Police (CFLP) in Warsaw and comprise approximately 2% of all opinions issued annually. Despite a relatively low workload in recent years, the interest of law enforcement agencies in the use of this type of analyses in the criminal proceedings is on the rise. This article presents three exemplary opinions issued in recent years at the CFLP. The first opinion relates to murder, whereby concrete slabs were used to commit the criminal act. The second is related to an agricultural machinery fire, whereby evidence included soil samples recovered at the scene and from the suspect’s clothing. The last opinion concerns the falsification of semi-finished products used for amber jewelry craftsmanship.

Biometric methods and their application in the Police investigation work

Biometrics is one of the basic detection techniques used in law enforcement activities on a daily basis. Like other techniques, it is constantly changing. This article aims to provide an overview of what was in the past, what is now, and what will be in the near future. It presents the selected methods of collecting some of the data, as well as the systems used to process them. In addition, practical guidance is provided on how individual biometric data should be collected and, for specific cases, it explains why the data collection procedure is carried out in one way and not another, and what it means for its subsequent processing. As problems sometimes arise during recovery of the material they have been presented together with an overview of the reasons for that. In addition to information on the technical aspects, the article also includes references to legal acts regulating issues related to biometrics.

Harnessing the potential of the environmental microbiome in forensic science

A scientific consortium led by the Central Forensic Laboratory of the Police has undertaken to develop a method for DNA analysis of the soil microbiome to be used in forensic investigations. The aim of the project entitled Soil Microbiome Analysis Forensic Tool – SMAFT (http://smaft.eu/), financed by the National Center for Research and Development (DOB-BIO10/03/01/2019), is to develop a new tool that enables the association of a trace in the form of a soil sample with a specific geographical location. The first part of the paper introduces the concept of the microbiome and presents the possibilities of using microbiome DNA analysis in forensic science. In the second part, the stages of the SMAFT project are described in detail, beginning from the collection of soil samples from different sites in Poland across all seasons and isolation of microbiome DNA through massively parallel sequencing (MPS) technology-based analysis of isolates and the development of a genetic test containing a set of metagenomic markers allowing for effective individualization of soil samples, up to the creation of an IT system enabling analysis and interpretation of the obtained results, which includes a database of soil microbiome DNA profiles from various locations in Poland.

Analysis of chainsaw cutting patterns

While timber thefts occur on both public and private lands, it is difficult to prevent illegal cutting of timber in large forested areas. However, when investigators encounter suspected stolen logs, it may be possible to match the cut ends of the logs to stumps in the forest. While cutting a tree, a chainsaw operator may change saw positions so different directional striation patterns on the cut end of a tree may be produced. In this study, 25 samples were cut from a recently harvested tree. Each sample was ~ 3–6 cm in thickness and approximately 11–15 cm in diameter. A Stihl Model 290 gasoline powered chainsaw with a chipper chain equipped with a 50 cm bar was used to cut the samples. Fifty cut ends were examined for directional striation changes on the cut end. A classification system was devised to characterize the different patterns.

Structural-spectroscopic analysis of DFO/PVA films as potential materials used in revealing fingerprints on non-porous surfaces.

1,8-diazafluoren-9-one (DFO) is a sensitive luminescent probe targeting α-amino acids. The study described herein exploited its physicochemical properties to form DFO/PVA polymer films. As a result, materials with stable and reactive DFO were obtained. Spectroscopic analysis of the formed films showed that the films with the highest concentration of DFO exhibited the highest reactivity. Novel materials in the form of thin DFO/PVA films with potential applications for revealing fingerprints on non-porous surfaces were obtained.

Digital forensics in the context of cloud computing data storage services

The role and capabilities of digital forensics in the cloud computing environment still remain an unsolved and insufficiently explored scientific area. The growing popularity of cloud-based data storage services makes recovery of evidence on the Internet a major challenge for forensic IT exminers. Existing legal barriers in most cases prevent direct access to cloud stored resources for the purpose of recovering data. In many situations, assistance from foreign law enforcement and judicial authorities is required. Findings made during forensic IT analysis that allow reconstructing user’s activities and indicate the act of taking advantage of cloud computing data storage is a justification for undertaking international cooperation. Therefore, it is important to know potential sources of information that enable the reconstruction of the activity of the user in cloud computing services, as well as the awareness of the current state of knowledge and scientific research in this field.

Expert witness in preparatory proceedings and his/her role in the investigation based on an example of a manslaughter case from 26 years ago.

The article is a case study of a manslaughter case that remained unsolved for over 26 years. In its content the role of forensic experts is emphasised as well as their significant impact on the effectiveness of conducting the preparatory proceedings under discussion. A closer look at the investigation shows that the detection process in the present case was mainly based on DNA profiling. The cooperation of police officers focusing on intelligence work and those who deal with investigative activities, the exchange of knowledge and experiences, as well as the ability to impartially once more look into the previously recovered traces and evidence was not without significance.

Sebaceous and sweat secretions and person’s age

The article presents results of the relationship between the quantity of sweat and sebaceous secretions and the age of a person. The study was carried out in a group of 70 persons of various ages and both sexes. Basing on the results it may be concluded that the age and sex have a significant influence on the quantity of sweat and sebaceous secretions. This can be used during preparation of various test samples, for example competence tests for fingerprint examiners.

A few remarks about the use of Griess reagent in firearm examinations

The purpose of this article is, inter alia, to determine whether it is possible to define the time that has elapsed since the last shot from a firearm, based on chemical tests of the post-firing residue remaining in the interior of the gun barrel after combustion of gunpowder and firing the primer mass, using Griess reagent. The article also presents the firearm examination findings related to the use of Griess reagent, including the risk of falsification of the results due to previous use of red fluorescent dye in dactyloscopic firearm examinations.