11 research outputs found

    Forensic Face Recognition: A Survey

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    Beside a few papers which focus on the forensic aspects of automatic face recognition, there is not much published about it in contrast to the literature on developing new techniques and methodologies for biometric face recognition. In this report, we review forensic facial identification which is the forensic experts‟ way of manual facial comparison. Then we review famous works in the domain of forensic face recognition. Some of these papers describe general trends in forensics [1], guidelines for manual forensic facial comparison and training of face examiners who will be required to verify the outcome of automatic forensic face recognition system [2]. Some proposes theoretical framework for application of face recognition technology in forensics [3] and automatic forensic facial comparison [4, 5]. Bayesian framework is discussed in detail and it is elaborated how it can be adapted to forensic face recognition. Several issues related with court admissibility and reliability of system are also discussed. \ud Until now, there is no operational system available which automatically compare image of a suspect with mugshot database and provide result usable in court. The fact that biometric face recognition can in most cases be used for forensic purpose is true but the issues related to integration of technology with legal system of court still remain to be solved. There is a great need for research which is multi-disciplinary in nature and which will integrate the face recognition technology with existing legal systems. In this report we present a review of the existing literature in this domain and discuss various aspects and requirements for forensic face recognition systems particularly focusing on Bayesian framework

    Forensic applications of analog memory: the digital evidence bag

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    Digital evidence is electronic data that \has the potential to make the factual account of either party more probable or less probable than it would be without the evidence" [1]. We consider digital evidence stored on a physical memory device, collected in the fi eld and transported to a lab where the digital content is stored and analyzed. Digital Forensics is the area of study that deals with the science behind this process, as well as establishing best practices and legal requirements. The core aspects of digital forensics are preserving evidence integrity and the chain of custody during the handling and storage of the evidence [2]. In this thesis, we look specifi cally at digital evidence where only digital data is collected (such as forensic photography), as opposed to digital evidence that also includes the storage medium (such as seized mobile phones). We review the existing procedures used for collecting and transporting evidence and explore how these processes could be improved to better suit this kind of digital evidence. The fi eld of Information Security deals with providing con fidentiality and integrity of data, along with authentication and non-repudiation of both data and entities [3]. This is a widely researched and well developed area with many commercial applications, the most well known being internet security. We review and categorize the existing technologies used in information security into four avenues of approach based upon the fundamental security concepts of each: cryptography, widely witnessed, hardware security and exploitation of manufacturing defects. Many information security systems incorporate several of these approaches which leads to the overall security of the system being improved. The aims of Digital Forensics and Information Security are similar, however the processes and systems used are very different. This partly reflects that digital forensics is usually subject to a greater level of legal scrutiny, but it also highlights that there are potentially opportunities to improve the processes and systems used. Hence we develop the concept of a \digital evidence bag" (DEB), a device for the secure transport of digital evidence that has the same requirements as physical evidence bags: tamper-evident, unforgeable and clean. To achieve these requirements through technological solutions, we look at technology used in Information Security along with traditional forensic processes and explore how they can be adapted to create a DEB. Given the nature of digital data, it is easy to produce exact copies and edit the data with- out loss of quality. From a forensics point of view, this strips out a lot of the imperfections that are usually exploited in the traditional forensic processes. However the technology used to build digital memory is still inherently analog and has non-ideal characteristics, which are usually obfuscated in the digital application space. We show how these characteristics can be exploited to achieve the DEB requirements. We explore how a digital fi ngerprint for conventional digital memory could be used to meet the requirements of the DEB. We also propose a DEB based on analog memory cells which offers a novel method to meet the requirements.Thesis (MPhil) -- University of Adelaide, School of Electrical and Electronic Engineering, 202

    Helping with inquiries: theory and practice in forensic science

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    This thesis investigates the reasoning practices of forensic scientists, with specific focus on the application of the Bayesian form of probabilistic reasoning to forensic science matters. Facilitated in part by the insights of evidence scholarship, Bayes Theorem has been advocated as an essential resource for the interpretation and evaluation of forensic evidence, and has been used to support the production of specific technologies designed to aid forensic scientists in these processes. In the course of this research I have explored the ways in which Bayesian reasoning can be regarded as a socially constructed collection of practices, despite proposals that it is simply a logical way to reason about evidence. My data are drawn from two case studies. In the first, I demonstrate how the Bayesian algorithms used for the interpretation of complex DNA profiles are themselves elaborately constructed devices necessary for the anchoring of scientific practice to forensic contexts. In the second case study, an investigation of a more generalised framework of forensic investigation known as the Case Assessment and Interpretation (CAI) model, I show how the enactment of Bayesian reasoning is dependent on a series of embodied, experiential and intersubjective knowledge-forming activities. Whilst these practices may seem to be largely independent of theoretical representations of Bayesian reasoning, they are nonetheless necessary to bring the latter into being. This is at least partially due to the ambiguities and liminalities encountered in the process of applying Bayesianism to forensic investigation, and also may result from the heavy informational demands placed on the reasoner. I argue that these practices, or 'forms of Bayes', are necessary in order to negotiate areas of ontological uncertainty. The results of this thesis therefore challenge prevailing conceptions of Bayes Theorem as a universal, immutable signifier, able to be put to work unproblematically in any substantive domain, Instead, I have been able to highlight the diverse range of practices required for 'Bayesian' reasoners to negotiate the sociomaterial contingencies exposed in the process of its application

    Understanding science in the courtroom: a multidimensional approach for measuring juror comprehension of statistical statements

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    Jurors are routinely required to understand, evaluate, and make important decisions with forensic science evidence in courts. How forensic practitioners should report their opinion evidence to optimise comprehension in courts has thus been the subject of widespread attention and debate in recent years. In Section 1 of this thesis, we report a descriptive study examining the reporting practices of forensic practitioners, which found that practitioners overwhelmingly favoured simple non-statistical categorical statements to report their opinions. However, these categorical statements conflict with standards of transparent, accurate, and scientifically robust reporting, and best practice recommendations now favour the use of statistical statements in courts. In light of best practice recommendations, a large body of research has been devoted to understanding how laypeople understand and respond to different types of statistical statements. However, this body of work has a number of notable conceptual and methodological limitations. In Section 2 of this thesis, we present seven experiments that aimed to address the limitations of existing literature by using a novel multidimensional approach to measuring individual-level comprehension of statistical statements. This approach operationalised comprehension as comprised of five indicators of comprehension used interchangeably in existing literature (consistent evidence evaluations, inferential ability, sensitivity to evidence strength, orthodox belief-updating, and coherent reasoning). Across our experiments, we found that different indicators of comprehension give different impressions of participant understanding, and that certain indicators (e.g., inferential ability) told us more about how laypeople would use statistical statements in their trial decisions than others. We observed there to be substantial variability in the levels and forms of comprehension shown by participants, and we found this to be largely unaffected by changes to statistical (or non-statistical) statement format. Together, these results clarify inconsistencies in existing research, provide a more nuanced understanding of lay comprehension of statistical statements, and lay a foundation for future research into how we can optimise the communication of statistical statements in courts

    Evaluating The Viability Of Obtaining Dna Profiles From Dna Encapsulated Within The Layers Of Counterfeit Banknotes

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    The use of digital printing has made the linking of counterfeit banknotes from the same organised crime groups difficult for law enforcement agencies and Central Banks. A more reliable and objective means of attributing counterfeits to a common source is therefore required. An area of potential forensic evidence could be from the acquisition of trace DNA encapsulated between the layers in a multilayer counterfeit or from the adhesive used for adhesive external features such as foil patches or foil strips. By establishing a novel method for the removal and extraction of DNA, the possibility of profiling encapsulated DNA from counterfeit euro banknotes could be evaluated. Preliminary research established that DNA could be removed from the adhesive side of dot matrix holograms using Chelex resin and phenol chloroform extraction. However, the percentage yield of DNA successfully extracted was low, with most results being below 20%. To increase the release of DNA from the adhesive layer of the dot matrix holograms, xylene, a 1,2-indandione working solution and ethanol were shown to be successful at separating the adhesive layers of two-layer counterfeits and on the adhesive used on dot matrix holograms present on some counterfeit banknotes. Xylene was applied in the swabbing of dot matrix holograms in a simulated procedural study involving the extraction of DNA through three extraction processes. Samples were then quantified and DNA profiled to establish the condition of present touch DNA. Both Chelex resin and phenol chloroform gave partial DNA profiles in the majority of samples, counter to what the qPCR data suggested in prior analysis. A modified Chelex resin extraction with ethanol-based swabbing was applied to seized counterfeit banknotes to show the potential of the methodology established. However, no profiles were successfully acquired from either the dot matrix holograms or the imitation metallic threads analysed. To account for a potential loss of DNA, direct PCR was carried out on segments of imitation metallic thread taken from 24 counterfeit banknotes. Two of the samples gave partial DNA profiles that had alleles that could be used for RMP analysis and one profile where the allelic peaks were challenging to interpret. Although no link between the DNA profiles could be established using profile comparisons, the results do highlight the potential of acquiring DNA profiles from DNA encapsulated in the layers of counterfeit banknotes. This research shows the capability of acquiring DNA from counterfeit banknotes for forensic investigations, which with further research could be part of a standard procedure for counterfeit banknote processing to gain intel on organised crime groups

    Advances in Forensic Genetics

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    The book has 25 articles about the status and new directions in forensic genetics. Approximately half of the articles are invited reviews, and the remaining articles deal with new forensic genetic methods. The articles cover aspects such as sampling DNA evidence at the scene of a crime; DNA transfer when handling evidence material and how to avoid DNA contamination of items, laboratory, etc.; identification of body fluids and tissues with RNA; forensic microbiome analysis with molecular biology methods as a supplement to the examination of human DNA; forensic DNA phenotyping for predicting visible traits such as eye, hair, and skin colour; new ancestry informative DNA markers for estimating ethnic origin; new genetic genealogy methods for identifying distant relatives that cannot be identified with conventional forensic DNA typing; sensitive DNA methods, including single-cell DNA analysis and other highly specialised and sensitive methods to examine ancient DNA from unidentified victims of war; forensic animal genetics; genetics of visible traits in dogs; statistical tools for interpreting forensic DNA analyses, including the most used IT tools for forensic STR-typing and DNA sequencing; haploid markers (Y-chromosome and mitochondria DNA); inference of ethnic origin; a comprehensive logical framework for the interpretation of forensic genetic DNA data; and an overview of the ethical aspects of modern forensic genetics

    Effect of visual feedback on the static and kinetic individual characteristics of handwriting

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    It has been previously established that handwriting is a motor skill defined in a two dimensional spatial domain, consisted of three major levels through which the motor units that contain the letter trajectories are retrieved from their motor memory storage and translated into a process of muscle commands via muscle adjustments. As soon as individuals start learning how to write they are introduced to a writing system common to a group of writers connected by geographic, academic, temporal, national or occupational links. As the writing ability evolves, writers distance themselves from the class system, that they were taught, develop peculiarities in handwriting and acquire personal writing characteristics, the so called individual characteristics of handwriting, which are considered the backbone of forensic handwriting identification. Handwriting is influenced by a number of genetic, physiological and biomechanical factors. Some factors can change the individual's writing so drastically that it may be impossible to make an accurate comparison of the person's normal writing with the person's abnormal writing causing serious problems for forensic document examiners. However the research regarding the visual feedback is partially contradictory regarding the degree of its influence on the individual characteristics. A two-pronged approach was designed in order to investigate the degree of this influence: Samples of signatures, cursive and block handwriting written with and without visual feedback were collected by 40 volunteers and were imported in a PC via an opaque pen tablet using an electronic inking pen. The data was stored and analyzed in a handwriting movement analysis software module specially designed for this research, that was attached in the software MovAlyzeR by Neuroscript LLC. Peer reviewed forensic comparison by a forensic document examined (FDE) between the two groups (that is the group of samples executed with normal visual feedback versus the group of samples executed without visual feedback) shows total lack of significant differences between samples of the two different conditions and the existence of a large corpus of similarities in the design and the pictorial aspect, regardless of the complexity of the samples. Focusing on the cursive and block handwriting, six traits linked to the absence of visual feedback where found: change of overall size, non uniformity of left margins, change of slant, avoidance of pen lifts, inclusion of extra trajectories and decrease of line quality. Furthermore, it was established that the absence of visual feedback by itself cannot lead a trained FDE to an erroneous conclusion. The statistical analysis shows that visual feedback significant influences the duration and average absolute velocity of the signature execution, since the signature is executed more slowly under no visual feedback. Further analysis of the cursive handwriting shows that without visual feedback there is a significant increase in absolute and horizontal size as well as average pen pressure and a decrease in slant and vertical size while in block handwriting there is a significant increase in absolute and horizontal size, average pen pressure as well as duration and a decrease in slant, average absolute velocity and vertical size. The comparative analysis suggests that the factors of gender, educational level and handedness creates an insignificant influence during the comparison of the two conditions of the researched individual characteristics, with the only notable exception of the relationship between signature duration and educational level due to automation and its results in the memory retrieval program of the allographs. The combination of the above findings suggests that all types of writing (signature, cursive and block handwriting) are governed by a single major open loop motor program, which is not significantly influenced by visual feedback -no evidence was found that visual feedback intervenes significantly in the procedure of allograph execution, but is mainly linked with the auxiliary order of macro-managing, inspection and possibly correction of the overall outcome of the combination of the above allographs

    The development of enhanced experimental strategies for the DNA analysis of low-template or compromised forensic sample types

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    Single-cell DNA analysis is not routinely carried out in a forensic setting as it is considered unreliable due to challenges associated with DNA amplification, contamination and profile interpretation. In light of the development of increasingly sensitive techniques, the question of the reliability of single-cell DNA analysis in terms of both processing and interpretation is addressed in the first part of this thesis. Optimising all stages of the DNA analysis process has provided a sensitive method which facilitates the successful outcome of a useable profile from single-cells. Although no consensus profile can be generated for this sample type, interpretation guidelines have been set to enable the robust analysis of single cells. It has been concluded that single-cells can be reliably amplified and profiled for forensic purposes. Both DNA and textile fibres have a proven track record in forensic casework yet their analysis is rarely combined. As an application of the aforementioned single-cell DNA analysis, this project explores the possibility that when fibres are transferred from one surface to another, they could also be acting as a vector for the wearer’s own DNA, through cells that have adhered to the fibre surfaces. Fluorescent staining and microscopy is used to detect the cells in situ on the fibre surface, which are then recovered and processed for DNA using the previously optimised single-cell analysis methods, along with a newly developed DNA assay designed for the amplification of low DNA template samples. The results of this study have demonstrated that cells can be visualised in situ on the fibre surface and that there is potential for cell transfer to occur. It has been concluded however, that from a casework point of view, targeting transferred fibres for cells may not be the best approach as it is time consuming and has not been shown to be effective in this study. The final part of this thesis is focused on the efficacy of massively parallel sequencing (MPS) technology for samples that are expected to be severely degraded due to age or exposure to a hostile environment. The ability of both the recently launched Illumina ForenSeq™ DNA Signature Prep Kit for nuclear DNA markers and an in-house method for the sequencing of degraded mitochondrial DNA, have been tested to determine if MPS offers a more comprehensive evaluation of degraded material than the traditional PCR-CE methods. The results of the ForenSeq kit have demonstrated the effectiveness of its low molecular weight STR and SNP markers for amplifying low template, degraded DNA samples, with alleles amplified using less than 20 pg total DNA input. This kit has also therefore shown application in the field of bioarchaeology, as it can provide the biological sex of the sample, biogeographic ancestry information and also aids detection of sample/control contamination. The in-house mitochondrial DNA assay resulted in the successful amplification and sequencing of samples for which no nuclear DNA was amplified. The high depth of read coverage in these samples, average of 18,000, allowed for the identification of even low level variants

    Tematski zbornik radova međunarodnog značaja. Tom 1 / Međunarodni naučni skup “Dani Arčibalda Rajsa”, Beograd, 3-4. mart 2015

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    Dear readers,In front of you is the Thematic Collection of Papers presented at the International Scientific Confer-ence “Archibald Reiss Days”, which was organized by the Academy of Criminalistic and Police Studies in Belgrade, in co-operation with the Ministry of Interior and the Ministry of Education, Science and Techno-logical Development of the Republic of Serbia, National Police University of China, Lviv State University of Internal Affairs, Volgograd Academy of the Russian Internal Affairs Ministry, Faculty of Security in Skopje, Faculty of Criminal Justice and Security in Ljubljana, Police Academy “Alexandru Ioan Cuza“ in Bucharest, Academy of Police Force in Bratislava and Police College in Banjaluka, and held at the Academy of Crimi-nalistic and Police Studies, on 3 and 4 March 2015.International Scientific Conference “Archibald Reiss Days” is organized for the fifth time in a row, in memory of the founder and director of the first modern higher police school in Serbia, Rodolphe Archibald Reiss, PhD, after whom the Conference was named.The Thematic Collection of Papers contains 168 papers written by eminent scholars in the field of law, security, criminalistics, police studies, forensics, informatics, as well as members of national security system participating in education of the police, army and other security services from Spain, Russia, Ukraine, Bela-rus, China, Poland, Armenia, Portugal, Turkey, Austria, Slovakia, Hungary, Slovenia, Macedonia, Croatia, Montenegro, Bosnia and Herzegovina, Republic of Srpska and Serbia. Each paper has been reviewed by two reviewers, international experts competent for the field to which the paper is related, and the Thematic Conference Proceedings in whole has been reviewed by five competent international reviewers.The papers published in the Thematic Collection of Papers contain the overview of contemporary trends in the development of police education system, development of the police and contemporary secu-rity, criminalistic and forensic concepts. Furthermore, they provide us with the analysis of the rule of law activities in crime suppression, situation and trends in the above-mentioned fields, as well as suggestions on how to systematically deal with these issues. The Collection of Papers represents a significant contribution to the existing fund of scientific and expert knowledge in the field of criminalistic, security, penal and legal theory and practice. Publication of this Collection contributes to improving of mutual cooperation between educational, scientific and expert institutions at national, regional and international level
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