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• S tability and regularity analysis of bare footprint measurements at different motion speeds. • Significant differences were found in length measurements (A1-A5). • MPJ and Calc width showed no significant differences across different speeds. • Mean length measurements decreased gradually as walking speed accelerated among young adults in eastern China. In some crime scenes, there may be bare footprints. Analyzing and testing the linear measurements of bare footprints in crime scenes can play an important role in personal analysis and individual identification. However, the linear measurements of bare footprints may be influenced by different motion states, leading to changes in length and width or even significant deviations. Previous studies focused on the linear differences between static and dynamic footprints, and failed to take the speed factor into consideration. This paper studied the stability and change regularities of the linear measurements of bare footprints in four different motion states: standing, normal walking, fast walking and trotting. Dust footprints of the right feet were collected from 80 healthy young adults under these four motion states. Seven linear measurements were obtained for each footprint using the Reel method, totaling 2240 data sets. One-way repeated measures ANOVA was used to assess the measurement variations across the four states. The results showed that there were statistically significant variances in the length measurements (A1-A5) between the standing state and other motion states, whereas no statistically significant variances were observed between the three dynamic states. It was found that the mean values of the five length measurements (A1–A5) increased from static to dynamic state, and then gradually decreased slightly as the walking speed increased. Additionally, no significant differences were found in the two width measurements (MPJ Width and Calc Width) between the four motion states. As a preliminary study, this study can provide a reference for the analysis of bare footprints in different motion states extracted from crime scenes. [ABSTRACT FROM AUTHOR]

DNA technology is the gold standard with respect to the identification of individuals from biological evidence. The technology offers the convenience of a universally similar approach and methodology for analysis across the globe. However, the technology has not realised its full potential in India due to the lack of a DNA database and lacunae in sample collection and preservation from the scene of crime and victims (especially those of sexual assault). Further, statistical interpretation of DNA results is non-existent in the majority of cases. Though the latest technologies and developments in the field of DNA analysis are being adopted and implemented, very little has been enacted practically to improve optimise sample collection and preservation. This article discusses current casework scenarios that highlight the pitfalls and ambiguous areas in the field of DNA analysis, especially with respect DNA databases, sampling, and statistical approaches to genetic data analysis. Possible solutions and mitigation measures are suggested. [ABSTRACT FROM AUTHOR]

• 150 mock jurors viewed bloodstain pattern analysis evidence. • Split into two groups, the test group also viewed a 3D flythrough of the scene. • The test group had significantly better knowledge retention. • There was no significant difference in emotion and confidence between the groups. There are numerous crime scene investigation applications of 3D scanning that have been previously documented. This paper documents the application of a 3D point cloud in the presentation of Bloodstain Pattern Analysis evidence to mock jurors. 150 mock jurors viewed a presentation of Bloodstain Pattern Analysis evidence from a murder trial in the UK. After viewing the evidence, the participants were tested on their knowledge of the evidence and repeated the test again 2 weeks later; to simulate criminal trial conditions; whereby there is a time lapse between the initial viewing of evidential material and deliberation. This paper found that the mock jurors who additionally viewed a 3D flythrough of a point cloud of the crime scene, better retained knowledge of the evidence over time, reported a greater ability to visualise the crime scene and had higher levels of interest in the evidence. Crucially, the 3D flythrough group did not report different levels of confidence in the accuracy of their memories of the evidence, nor different levels of emotional arousal to the group that viewed the evidence without the 3D presentation. Together, these findings suggest that 3D scanning of crime scenes, and the resultant point cloud's presentation to jurors, could add further value to the justice system when spatial information, such as Bloodstain Pattern Analysis evidence, is presented. [ABSTRACT FROM AUTHOR]

• Ghosting occurred most frequently on the 1st and 2nd toe of the footprint. • Ghosting was present on all ten toes of the footprints in only 2.94% of participants. • Footprint measurements with ghosting are significantly higher. • More accurate estimates of stature are from measurements with ghosting. In cases where multiple footprints are found at a crime scene, it is unusual that all are static, and some are likely dynamic. Depending on how the footprint was made, we distinguish between dynamic and static footprints. A distinguishing feature that has only recently been associated with dynamic footprints is the fact that dynamic footprints differ from static footprints by the presence of additional markings around the back of the heel and the tops of the toe prints, the so-called ghosting phenomenon. The present study aims to analyse the ghosting phenomenon on dynamic footprints – its occurrence in relation to sex, laterality, and different areas of footprints as well as length features. Additionally, it aims to investigate the assessment of the ghosting phenomenon on dynamic footprints when estimating stature for biological profiling in the forensic field. The study sample comprised of 170 young adults aged 18 – 30 years of both biological sexes. Stature was measured and dynamic footprints were obtained where the ghosting phenomenon was analysed together with length measurements of the same footprint with and without ghosting. In the first and second toes of footprints, the ghosting phenomenon occurred most frequently in both sexes and in the sex-mixed group. Sex differences were not significant in ghosting occurrence on right and left footprints (p > 0.05), except for the area of the left fifth toe (p = 0.045). All the footprints' lengths with ghosting were significantly higher (p < 0.001) than those without ghosting. Statures calculated from footprint length measurements with ghosting predicted stature more accurately than statures calculated from the same footprint length measurements without ghosting. In the case of finding dynamic footprints at crime scenes, it is necessary to correctly identify and evaluate ghosting of the footprint. This comparison can be helpful in interpreting how ghosting should be taken into account when estimating a person's stature. [ABSTRACT FROM AUTHOR]

• Crime scene investigation training and education has to address specific problem solving and psychomotor skills. • AR technology could improve current training and education approaches when used as a supplementary tool. • Potential challenges and considerations are highlighted that are to be explored before implementing AR technology. The role of the crime scene investigator is complex, and investigators need to be able to conduct multiple frequently performed tasks. Appropriate training and education are critical to impart the crime scene investigator with the necessary capabilities. For a range of reasons, including the COVID-19 pandemic and the need for multi-disciplinary capabilities, training and education requirements have evolved in recent times to be more flexible and accessible. The skills of a crime scene investigator can be broadly categorised into two types of fundamental skills: decision-making and psychomotor skills. Both these skills need to be taught and assessed within training and education programs. The most common approach to impart these skills is by incorporating a crime scene simulation facility; however, not everyone has access to these facilities. Furthermore, crime scene staff often undertake refresher courses and are required to complete proficiency assessments. Conducting these activities in a dedicated crime scene simulation facility is time consuming and costly. Virtual tools have been developed in recent years to address this, but these tools only assess decision-making skills and not psychomotor skills. This paper argues that the implementation of augmented reality (AR) technology should be considered in crime scene investigator training and university education, because it can provide significant advantages when paired with conventional methods of training and education. When appropriately managed, AR can provide an avenue of training where both decision-making and psychomotor skills can be addressed simultaneously, while providing a more flexible and accessible approach. The implementation of AR has the potential to significantly improve the standards of teaching, resulting in better equipped crime scene investigators. The paper will explore how AR has the potential to improve accessibility of training, increase safety, enhance the student experience, enhance collaboration and feedback through connectivity and potentially reduce cost. This paper will also provide an insight into what would need to be considered before implementing AR technology into crime scene investigation training and education alongside current approaches. It is argued that the inclusion of AR into the current training and education arsenal provides significant benefits that are worthy of exploration. [ABSTRACT FROM AUTHOR]

• This case report shows how databases can be used to determine likelihood ratios. • The evaluation of a two-way transfer is detailed. • Using evaluative reporting allows for a transparent conclusion to court. In forensic paint examination, paint traces retrieved on a crime scene are regularly compared to painted objects seized from a suspect. Less often, traces are only observed on the seized objects and compared to a damaged painted object on the crime scene. In some specific cases, paint traces may be found both on the crime scene and on one or multiple seized painted objects. The latter may be the result of a cross-transfer that occurred during the illicit act. However, mere coincidence is another possible explanation for these observations and may not be neglected. Proper consideration of the relevant populations and sufficient analytical data permits the evaluation of the results given activity level propositions. This allows the forensic expert to present a transparent and well-balanced statement on the value of their findings concerning the disputed issues in court. [ABSTRACT FROM AUTHOR]

• Investigates previously unknown ethical issues in forensic entomology. • Examines the application of Codes of Ethics in Forensic Entomology. • Places a premium on interdisciplinary collaboration to promote transparency and sustain ethics. This article investigates a critical part of professional careers: adhering to a code of ethics that defines proper behavior within the context of one's specialized practice. It aims to improve the setting of forensic entomology work by highlighting the ethical issues that frequently emerge. The primary goal is to uncover common ethical issues involved in this field's everyday activities and provide informed advice on appropriate resolution options. This investigation dives into the complex interaction of religious beliefs, cultural aspects, and issues of ethics, evaluating their relevance in forensic entomology. It examines a wide range of ethical issues, from the ethics involved in collecting samples at crime scenes and morgues to the ethics created into scientific investigations, report writing, and court testimony. These guiding principles are critical in setting scientific standards and building public trust in forensic entomology's ability to provide exceptional services. Notably, regardless of whether the forensic entomology service provider is accredited by any validating organization, these ethical requirements remain critical, emphasizing their global application. [ABSTRACT FROM AUTHOR]

• Varied hypothetico-deductive reasoning styles impact trace search and collection. • CSIs could benefit from external knowledge for investigation's many decision points. • There is no clear consensus over how much information CSIs should receive. • CSIs need better tools to aid in reasoning processes and improve CSI outcomes. Crime scene investigations are highly complex environments that require the CSI to engage in complex decision-making. CSIs must rely on personal experience, context information, and scientific knowledge about the fundamental principles of forensic science to both find and correctly interpret ambiguous traces and accurately reconstruct a scene. Differences in CSI decision making can arise in multiple stages of a crime scene investigation. Given its crucial role in forensic investigation, CSI decision-making must be further studied to understand how differences may arise during the stages of a crime scene investigation. The following exploratory research project is a first step at comparing how crime scene investigations of violent robberies are conducted between 25 crime scene investigators from nine countries across the world. Through a mock crime scene and semi-structured interview, we observed that CSIs have adopted a variety of investigation approaches. The results show that CSIs have different working strategies and make different decisions when it comes to the construction of relevant hypotheses, their search strategy, and the collection of traces. These different decisions may, amongst other factors, be due to the use of prior information, a CSI's knowledge and experience, and the perceived goal of their investigation. We suggest the development of more practical guidelines to aid CSIs through a hypothetico-deductive reasoning process, where (a) CSIs are supported in the correct use of contextual information, (b) outside knowledge and expertise are integrated into this process, and (c) CSIs are guided in the evaluation of the utility of their traces. [ABSTRACT FROM AUTHOR]

• Mueller polarimetry develops latent fingerprints and removes their backgrounds. • The procedure is non-destructive, so it preserves evidence for further analysis. • The method is flexible and robust against measurement errors. • The proposed instrument is inexpensive which makes it accessible for any crime lab. • The Mueller polarimeter is portable so it is suitable for crime scene work. In this article we have explored the use of Mueller polarimetry for the simultaneous and non-destructive latent fingerprint development and background elimination. This proposal not only expands previously reported uses of the polarization state of light for fingerprint development, but offers some advantages. Samples of a few donors, taken on different heavily back grounded substrates, were measured and processed. Several strategies for background removal were applied. The results are very promising, since the background was successfully erased in all cases and the quality of the developed fingerprints was excellent for most substrates and donors. Considering that the method is non-destructive and that the proposed measurement instrument is inexpensive and portable the method could be tried in real cases with no risk for the evidence. In addition, the success of the procedure for background removal raises the possibility of exploring if it would work for the enhancement of fingerprints developed with other methods. [ABSTRACT FROM AUTHOR]

• RACs in dust impressions were similar size/larger than their test impression mates. • RACs with positional and geometric similarity occurred between unrelated outsoles. • A minimum of 3.1% of shoes had a non-zero RAC-RMF based on features = 2.8 mm. • A maximum of 32% of shoes had a non-zero RAC-RMF based on features of any size. This study serves as Part II of an investigation into the random match frequency of randomly acquired characteristics (RAC-RMF) in footwear evidence. In Part I, RAC-RMF was estimated in a dataset of laboratory-simulated crime scene impressions deposited in blood. For Part II, a second dataset was created composed of impressions deposited in dust on paper or tile, with the latter lifted using gelatin or Mylar film. A total of 1,513 RACs were identified from more than 160 dust impressions and compared to RACs with positional similarity in test impressions from 1,299 non-mated outsoles. RACs of any size deposited in dust exhibited a 31% decrease in shoes with non-zero RAC-RMFs as compared to their mated test impressions, while those deposited in blood exhibited a 45% increase. When only considering shoes with at least one RAC deemed forensically-reliable (length ⩾ 2.8 mm), 3.1% of shoes contributing dust impressions and 3.4% of shoes contributing blood impressions exhibited relative RAC-RMFs at a value ⩾ 0.0008. Although each dataset resulted in a comparable rate for encountering non-zero RAC-RMFs, the estimate for dust was based on twice the number of RAC comparisons (154,477) than those performed when assessing blood (77,566). While these results are considered specific to the non-mated impressions and methods of analysis described herein, and continued work is required before rates can be fully understood and reported in forensic casework, this study encountered non-zero RAC-RMFs for shoes exhibiting at least one forensically-reliable RAC at a more frequent rate than any estimates previously reported. [ABSTRACT FROM AUTHOR]

• RACs in blood impressions were often smaller than their test impression mates. • RACs with positional and geometric similarity occurred between unrelated outsoles. • A minimum of 3.4% of shoes had a non-zero RAC-RMF based on features = 2.8 mm. • A maximum of 34% of shoes had a non-zero RAC-RMF based on features of any size. The aim of this study was to estimate random match frequency of randomly acquired characteristics (RAC-RMF) for laboratory-simulated crime scene impressions. Part I of this investigation reports this metric using a dataset of more than 160 questioned impressions created in blood and deposited on tile. A total of 759 RACs were identified in the blood impressions and compared to RACs with positional similarity in test impressions from 1,299 unrelated outsoles. Geometric similarity was quantified using a combination of visual comparisons and mathematical modeling based on percent area overlap. Results indicated that RACs in blood impressions were typically smaller, and therefore exhibited a two-thirds increase in the number of indistinguishable pairs compared to their mated test impressions. For shoes contributing at least one RAC, relative RAC-RMF values ⩾ 0.0008 were encountered at a rate between 3.4% and 34% for the blood impressions examined in this study. Part II of this investigation provides analogous results based on dust impressions deposited on paper and tile. Although the results in Part I and Part II are specific to randomly acquired characteristics and do not translate into an impression-wide RMF estimate, this research shows that RACs in questioned impressions of the type expected in casework co-occur in position and geometry with RACs in non-mated test impressions. Since theoretical models have traditionally been the basis for estimating RAC-RMF in footwear, the overall contribution of this research to the forensic footwear community is a calibration of this estimate based on empirical data. [ABSTRACT FROM AUTHOR]

• TiO 2 -coated self-cleaning glasses are challenging substrates for trace DNA analysis. • TiO 2 -coated glasses, Bioclean® and SaniTise™, most likely degrade trace DNA via photocatalysis. • Rapid trace DNA sample collection reduces impact of photocatalytic DNA degradation. Titanium dioxide (titania, TiO 2) is frequently used as a coating for a variety of self-cleaning products, such as antifogging vehicle mirrors, ceramic tiles, and glass windows because of its distinct physiochemical features. When exposed to light TiO 2 causes photocatalytic decomposition of organic contaminants, potentially compromising DNA integrity. The impact of TiO 2 -coated commercial glasses, Bioclean® and SaniTise™, on trace DNA persistence, recovery, and profiling was investigated. DNA in saliva and touch samples deposited on self-cleaning glass slides exposed to indoor fluorescent light for up to seven days was more degraded than control samples indicating some degree of fluorescent light-induced photocatalytic activity of the self-cleaning surfaces. When exposed to sunlight, DNA yields from saliva and touch samples deposited on the titania-coated substrates decreased rapidly, with a corresponding increase in DNA degradation. After three days no DNA samples applied to self-cleaning glass and exposed to natural sunlight yielded STR profiles. These results suggest that the photocatalytic activation of TiO 2 is the likely mechanism of action underlying the extreme DNA degradation on the Bioclean® and SaniTise™ glasses. Consequently, rapid sample collection and use may be warranted in casework scenarios involving TiO 2 -coated materials. [ABSTRACT FROM AUTHOR]

• Odors are valuable memory cues and can act as memory triggers. • We tested if odor exposure can aid recall of a virtual reality crime scene. • The crime scene content recall was tested in a free recall and a forced-response test. • We found no significant effects of odor exposure on a virtual crime scene recall. Environmental context reinstatement has a particular value for recall of information in forensic interviews. Since odors are valuable memory cues and can act as memory triggers, in our preliminary study we explored whether odor exposure can help people recall details of a crime scene. The study comprised 58 women and 15 men aged 22–35 who immersed in a carefully controlled environment closely resembling an actual crime setting, i.e., a virtual reality crime. Participants were exposed to an odor at encoding, recall, both or neither of these instances, yielding a total of 4 experimental groups that further completed a memory recall task. The crime scene content recall was tested in a free recall and a forced-response test immediately after seeing the crime scene and one month later. We found no significant effects of odor exposure on the free or the cued recall of the crime scene. The memory scores correlated neither with the self-assessed olfactory/visual sensitivity of the subjects, nor with the perceived odor pleasantness. These preliminary findings suggest that introduction of a vanilla odor while encoding and recalling a crime scene does not aid witness recall accuracy. [ABSTRACT FROM AUTHOR]

• Using machine learning and computer vision for automatic shoeprint image retrieval. • Automated crime scene linking with shoeprint images. • Advance performance for shoeprint image retrieval process. A shoeprint image retrieval process aims to identify and match images of shoeprints found at crime scenes with shoeprint images from a known reference database. It is a challenging problem in the forensic discipline of footwear analysis because a shoeprint found at the crime scene is often imperfect. Recovered shoeprints may be partial, distorted, left on surfaces that do not mark easily, or perhaps come from shoes that do not transfer marks easily. In this study, we present a shoeprint retrieval method by using a convolutional neural network (CNN) and normalized cross-correlation (NCC). A pre-trained CNN was used to extract features from the pre-processed shoeprint images. We then employed NCC to compute a similarity score based on the extracted image features. We achieved a retrieval accuracy of 82% in our experiments, where a "successful" retrieval means that the ground truth image was returned in the top 1% of returned images. We also extend our shoeprint retrieval method to the problem of linking shoeprints recovered from crime scenes. This new method can provide a linkage between two crime scenes if the two recovered shoeprints originated from the same shoe. This new method achieved a retrieval accuracy of 88.99% in the top 20% of returned images. [ABSTRACT FROM AUTHOR]

• Crime scene investigators' (CSIs) collection of traces is studied using heat maps. • CSI's collection of blood is impacted by awareness of limited resources. • Irrelevant contextual information indicating homicide or suicide biases trace collection. • CSI's trace collection show both similarities and differences with that of novices. When crime scene investigators (CSIs) encounter crime scenes with large volumes of blood, some selection and prioritization is often needed, and this will impact on what blood is and is not available for forensic analysis. What factors influence CSIs decision making process is largely unknown. This study examines the effects of awareness of limited resources and irrelevant contextual case information indicating either a homicide or a suicide on CSIs collection of blood traces. To this end, two scenario-based experiments with CSIs and novices were conducted. Overall, the results suggest that even when CSIs decisions are made under identical conditions, their trace selection varies both when it comes to numbers and locations. Furthermore, awareness of limited resources made CSIs collect fewer traces and their selections also varied following the contextual case information, showing similarities and differences with novices. Since blood traces can be used to establish both activity and identity the findings can have important implications for the subsequent investigation as well as trial. [ABSTRACT FROM AUTHOR]

• Development of the systematic Standard Operating Procedure using photogrammetry technology to reproduce the indoor scene in Virtual Reality accurately. • Early and accurate crime scene visualisation enables investigative teams to conduct a fast, agile, and informed decision-making process. • The accurate documentation of a crime scene is paramount as part of the recording process associated with the assurance of the continuity of evidence required by the courts. Early and accurate visualisation of a crime scene is highly desirable such that a rapid, agile, and informed decision-making process can be undertaken by an investigative team. We present a new standard operating procedure for imaging an indoor scene using DSLR cameras conventionally used by crime scene investigators and examiners. The standard operating procedure (SOP) enables the systematic photography of indoor spaces in such a way that the Structure from Motion (SfM) photogrammetry technique can be implemented, allowing the scene to be recreated in Virtual Reality (VR). To demonstrate the method's validity, we compare two VR-rendered representations of an example scene using (a) photographs taken by an experienced crime scene examiner using a conventional photographic method and (b) photographs taken by a novice photographer following the developed SOP. [ABSTRACT FROM AUTHOR]

• Botanical materials have potential to be used as forensic evidence. • Forensic experts work with plant remains more frequently than with whole specimens. • Pig carcasses are a common model for experiments in forensic mycology. • Diatom tests can confirm a post-mortem drowning. • Forensic botany is routinely used in the criminal investigations in few countries. Plants are a good source of biological forensic evidence; this is due to their ubiquity, their ability to collect reference material, and their sensitivity to environmental changes. However, in many countries, botanical evidence is recognised as being scientifically. Botanical evidence is not mostly used for perpertration, instead it tends to serve as circumstantial evidence. Plant materials constitute the basis, among others, for linking a suspect or object to a crime scene or a victim, confirming or not confirming an alibi, determining the post-mortem interval, and determining the origin of food/object. Forensic botany entails field work, knowledge of plants, understanding ecosystem processes, and a basis understaning of geoscience. In this study, experiments with mammal cadavers were conducted to determine the occurence of an event. The simplest criterion characterising botanical evidence is its size. Therefore, macroremains include whole plants or their larger fragments (e.g. tree bark, leaves, seeds, prickles, and thorns), whereas microscopic evidence includes palynomorphs (spores and pollen grains), diatoms, and tissues. Botanical methods allow for an analysis to be repeated multiple times and the test material is easy to collect in the field. Forensic botany can be supplemented with molecular analyses, which, although specific and sensitive, still require validation. [ABSTRACT FROM AUTHOR]

• Holistic review of the sexual assault investigative process. • Complete bioanalytical workflow emphasising recovery and examination of evidence. • Prosecution numbers falling despite little change in forensic support. • Literature supports RapidDNA testing at SARC or by Police. • Post-covid familiarity of lateral-flow tests mean victims could test own swabs. Sexual assault casework requires the collaboration of multiple agency staff to formalise an investigative pipeline running from crime scene to court. While the same could be said of many other forensic investigations, few require the additional support of health care staff and the combined forensic involvement of body-fluid examiners, DNA experts and analytical chemists. The sheer amount of collaborative effort between agencies is laid out through a detailed examination of the investigative workflow from crime scene to courtroom with each step in the pipelines detailed and discussed. Beginning with a review of sexual assault legislation in the United Kingdom this article details how sexual assault investigations are initiated by police and supported by sexual assault referral centre (SARC) staff who are often the first responders providing primary healthcare and patient support to victims while simultaneously collecting and assessing forensic evidence. Detailing the myriad of evidential material that can be documented and collected at the SARC, the review identifies and categorises key forensic tests to first detect and identify body-fluids recovered from evidence through to the secondary analysis of DNA to help identify the suspect. This review also focusses on the collection and analysis of biological material used to support the allegation that the sexual activity was non-consensual and provides a breakdown of common marks and trauma as well as a review of common analytical methods used to infer Drug Facilitated Sexual Assault (DFSA). The culmination of the investigative pipeline is discussed by reviewing the Rape and Serious Sexual Assault (RASSO) workflow used by the Crown Prosecution Service before providing our thoughts on the future of forensic analysis and possible changes to the described workflows. [ABSTRACT FROM AUTHOR]

• Incorporating simulated crime scenes at undergraduate institutions. • Use of inquiry-based, active, and cooperative learning in forensic sciences. • High impact practices in forensic science pedagogies. • Teaching forensic science with limited resources. Incorporating a simulated crime scene into one's pedagogy in forensic science undergraduate courses allows students the opportunity to experience a realistic scenario while demonstrating their knowledge and enhancing their critical thinking skills. The purpose of this paper is to examine an active learning approach to using simulated crime scenes to provide an impactful learning experience for students. While potentially challenging for the instructor, constructing a crime scene scenario can provide students with hands-on practical experience while helping to dispel forensic science misconceptions. Through many years of creating crime scenes, best practices for using such high impact activities in forensic science courses are described in detail, including preparatory exercises that culminate in the final crime scene scenario, considerations in preparing and constructing a crime scene activity, and supervising and assessing students once the activity begins. Three major challenges to implementing active learning exercises such as simulated crime scenes in undergraduate forensic science programs include high workload for instructors, limited supplies, and lack of suitable facilities. Workload solutions include instructors and departments considering the cost and benefit of course releases to improve curriculum and student enrollment. Supplies and facilities solutions involve innovation in reuse and repurposing of supplies, and instructor flexibility in using classroom and outdoor spaces. [ABSTRACT FROM AUTHOR]

Despite enhanced forensic collaborations between law enforcement agencies and universities, crime scene management remains a domain seen more as technical than scientific, largely carried out by sworn police officers qualified as scene of crime officers (SOCOs), confining forensic graduates to specialized expertise fields. Under such circumstances, we must ask ourselves why and how do we provide a generalised dedicated course to academic pupils who are not primarily intended to join such teams, excepting sometimes to assist them on a specialized field (explosion, arson, etc.)? Currently in Quebec, forensic graduates cannot join crime scene units attached to police forces, mainly because of unions, which argue about the need to be an experienced police officer before qualifying for a crime scene course. Based on the operational experience of the author, who created the foundational graduate forensic programme in Quebec, Canada, this paper will explain why such an academic course is still of high importance, its rationale within an academic curriculum, its goal and its implementation. Challenges are still to be considered, but selected feedback from students who understood that the aim of this course is distinct from their formal support disciplines, encourage such an approach. [ABSTRACT FROM AUTHOR]

• Forensic case investigation is taught through problem-based learning activities. • Digital technologies allow for simulating some parts of a forensic case investigation. • Digital tools facilitate this teaching to large student cohorts. • Digitised activities promoted students' critical thinking. • Blended teaching with on-line and on-site activities is more efficient. Forensic practice is the concluding practical course of the forensic science bachelor program at the School of Criminal Justice of the University of Lausanne. Learning activities are constructed around five main objectives for the resolution of simulated forensic case problems: 1) select relevant traces and items to be collected at the scene and perceive their potential value in the reconstruction process, 2) apply appropriate detection techniques in sequence to obtain clues of good quality, 3) process traces using Analysis, Comparison, Evaluation and Verification (ACE-V) methodology, 4) produce and summarise information in oral and written forms to help an investigation, and 5) work collaboratively to benefit from the diversity of group members. Simulating and supervising realistic activities is a complex task that became more and more challenging with a continuously increasing number of students over the years (from ca. 30 in 2016 to more than 60 in 2021). Thus, an educational innovation project was launched and aimed at implementing digital technologies to support the teaching staff. A computer-based crime scene simulation tool (allowing students to visualize 360° crime scenes and relevant items) and a communication tool (to simplify and centralise the communication between the students and the teaching staff) were implemented. This article describes the implementation, added value and limitations of these digital technologies in problem-based learning activities. Prior to 2020, the practical course forensic practice was delivered entirely on-site without specific technologies, and entirely on-line in 2020 (due to the sanitary restrictions related to the COVID-19 pandemic). Finally, in 2021, on-line and on-site activities were implemented with success, combining the best of both approaches in a blended teaching mode. An overall increase in the satisfaction of students and teaching staff was observed with the implementation of these tools. Limiting presence on-site allowed students to take a step back from the activities and collected items. This promoted critical thinking, and together with an increase in structured (on-line and on-site) interactions allowed for a positive, continuous learning experience. While the evaluations of these novel technologies were very positive, students still expressed their willingness to perform certain tasks on-site and a preference for face-to-face interactions. [ABSTRACT FROM AUTHOR]

• Three different types of TreadMatch (TM) scans were compared with validated test marks. • Dynamic TM footwear scans showed good repeatability compared with test marks. • Zoomed TM scans were as reliable as dynamic TM scans. • Hand-rolled TM footwear scans are not as reliable as dynamic TM scans. • Using TM for preliminary footwear comparisons could save time and resources. Currently in the UK, if a person is arrested or charged with a recordable offence, they can have prints of their footwear taken whilst in custody. The tread pattern recorded in these prints can be searched for using the National Footwear Database to find out if the same footwear pattern has been recovered at previous crime scenes, generating forensic intelligence. TreadMatch is a digitised system for collecting footwear prints seized from detainees in custody for this purpose. Whilst its use for generating intelligence is accepted, validation experiments have not been conducted to understand its level of performance in assisting in forensic comparison purposes for identification, because in the absence of an incorporated scale, it is not known how well TreadMatch reproduces the pattern size of a tread, threatening the validity of the comparison. If it can be determined that the measurements of TreadMatch scans are consistent with the more commonly used aluminium powder test marks, this could save Police time and resources if the digital scans could be used for preliminary assessment prior to the footwear being physically submitted for evidential comparison. Therefore, this study set out to compare three different types of TreadMatch scans ('dynamic', 'zoomed' and 'rolled') for thirty different pieces of footwear, with test marks of the same footwear using the traditional method (fingerprint powder). Length and width measurements were obtained from each tread pattern using GNU Image Manipulation Program software. The resulting data were analysed to assess for agreement between TreadMatch scans and test marks using 95% Intraclass Correlation Coefficients (ICC) and 95% Bland-Altman plots of Limits of Agreement (LOA). Additionally, an intra-sample study using fifteen repeated measurements of the same piece of footwear for different TreadMatch scanning methods was carried out to support the larger validity study. 95% ICC 3,1 resulted in coefficients ranging from 0.99 to 1.00 across all measurements. 95% LOA displayed close agreement. There was less agreement and more variation displayed between the test marks and the TreadMatch rolled scans for both length and width measurements. This variation for hand-rolled prints must be taken into consideration and a standard approach developed. The study suggests TreadMatch can be used for preliminary assessments in assisting forensic comparisons, particularly for dynamic and zoomed prints. [ABSTRACT FROM AUTHOR]

• Biological traces are widely present in forensic casework. • Current examination methods provide limited information about the trace. • A historical review of the forensic examination of biological traces can help understand how research is addressing these limitations. • Novel techniques may unlock previously unknown information from these traces. Forensic investigation involves gathering the information necessary to understand the criminal events as well as linking objects or individuals to an item, location or other individual(s) for investigative purposes. For years techniques such as presumptive chemical tests, DNA profiling or fingermark analysis have been of great value to this process. However, these techniques have their limitations, whether it is a lack of confidence in the results obtained due to cross-reactivity, subjectivity and low sensitivity; or because they are dependent on holding reference samples in a pre-existing database. There is currently a need to devise new ways to gather as much information as possible from a single trace, particularly from biological traces commonly encountered in forensic casework. This review outlines the most recent advancements in the forensic analysis of biological fluids, fingermarks and hair. Special emphasis is placed on analytical methods that can expand the information obtained from the trace beyond what is achieved in the usual practices. Special attention is paid to those methods that accurately determine the nature of the sample, as well as how long it has been at the crime scene, along with individualising information regarding the donor source of the trace. [ABSTRACT FROM AUTHOR]

[Display omitted] • First study to report differentiation of foundation creams based on NIR spectroscopy and chemometrics. • 93% of spectra identified correctly using NIR and PCA-LDA. • Darker foundations shades tend to be classified less accurately than lighter ones. • Different substrates did not affect differentiation Accuracy, Sensitivity, or Specificity. • A rapid, non-destructive method of identifying cosmetic trace evidence. Cosmetic smears are a form of trace evidence that can link the crime scene, suspects, and victims. Foundation and lipstick are the most common sources of cosmetics that can easily smear, with most current research focused on the evidential analysis of lipsticks. This research aims to create a database of cosmetic foundations on different materials and to access the robustness of using Near-infrared with chemometrics as a non-destructive technique to identify unknown samples collected from a crime scene. Small amounts of six shades of three brands of foundations were smeared on clothing materials, which were then analysed with a combination of Near-infrared with chemometric analysis. Principle component analysis (PCA) was used to reduce data dimensionality and explore potential patterns in sample separation and Linear Discriminant Analysis (LDA) was utilised to assign unknown samples to one of the established classes. The selected techniques proved to be promising for database construction and as a preliminary method of analysis, with 93% of the spectra being correctly classified. Notably, darker foundation shades were less likely to be correctly classified (90% classified correctly) compared to lighter ones (96.7% classified correctly). This could not be improved with Standard Normal Variate (SNV) data pre-treatment or selecting specific NIR regions. This finding is of particular importance; according to the Crime Survey for England and Wales (year ending March 2020) police recorded sexual offences demonstrated that those in Mixed and Black or Black British ethnic groups were significantly more likely to be a victim of sexual assault compared to White, Asian or Other ethnic groups. It is, therefore, crucial to add a wide range of foundation shades, particularly of darker tones, to the future database. [ABSTRACT FROM AUTHOR]

• Highly probative contributor STR genotype information recovered from complex mixtures by direct single cell subsampling (DSCS) and probabilistic genotyping (PG) with replicate analysis. • STRmix™ was validated for use with single cells. • Replicate analysis of single cells often allows for full STR genotype information recovery comparable to reference profiles. • DSCS reduces genotype information loss seen in standard mixture analysis. DNA mixtures are a common source of crime scene evidence and are often one of the more difficult sources of biological evidence to interpret. With the implementation of probabilistic genotyping (PG), mixture analysis has been revolutionized allowing previously unresolvable mixed profiles to be analyzed and probative genotype information from contributors to be recovered. However, due to allele overlap, artifacts, or low-level minor contributors, genotype information loss inevitably occurs. In order to reduce the potential loss of significant DNA information from donors in complex mixtures, an alternative approach is to physically separate individual cells from mixtures prior to performing DNA typing thus obtaining single source profiles from contributors. In the present work, a simplified micro-manipulation technique combined with enhanced single-cell DNA typing was used to collect one or few cells, referred to as direct single-cell subsampling (DSCS). Using this approach, single and 2-cell subsamples were collected from 2 to 6 person mixtures. Single-cell subsamples resulted in single source DNA profiles while the 2-cell subsamples returned either single source DNA profiles or new mini-mixtures that are less complex than the original mixture due to the presence of fewer contributors. PG (STRmix™) was implemented, after appropriate validation, to analyze the original bulk mixtures, single source cell subsamples, and the 2-cell mini mixture subsamples from the original 2–6-person mixtures. PG further allowed replicate analysis to be employed which, in many instances, resulted in a significant gain of genotype information such that the returned donor likelihood ratios (LRs) were comparable to that seen in their single source reference profiles (i.e., the reciprocal of their random match probabilities). In every mixture, the DSCS approach gave improved results for each donor compared to standard bulk mixture analysis. With the 5- and 6- person complex mixtures, DSCS recovered highly probative LRs (≥1020) from donors that had returned non-probative LRs (<103) by standard methods. [ABSTRACT FROM AUTHOR]

• Blood recovered from snow can yield viable DNA profiles suitable for court. • Various substrates commonly used by Forensic Identification Officers are sufficient mediums for recovering high yield blood from snow, where replicates performed consistently. • Slight variability in DNA yields and genotyping performance across the three substrates was observed, attributable to differences in methodology/evidence collection. Successful DNA typing of forensically relevant evidence is reliant on both the quality and quantity of biological material recovered from a crime scene. In geographical areas of the world exposed to cold climates, it is not uncommon for biological evidence to encounter a diversity of challenging surfaces and environments, including snowy surfaces. Currently, there is no standard protocol for recovery of bloodstain evidence in snow and very few publications exploring adequate methods of recovering biological evidence from snowy surfaces. In this study, three common substrates (e.g., cotton swabs, FTA paper, and untreated filter paper) utilized by investigators for evidence recovery were evaluated for their ability to recover human blood (DNA) evidence from snow that would be viable for traditional forensic DNA typing. Each biological sample was extracted and quantified to evaluate the quality and quantity of DNA recovered. All samples yielded sufficient non-degraded DNA to proceed with DNA profiling, where complete DNA profiles were generated from each collection substrate. The experimental findings presented herein demonstrate that the ability to recover viable DNA from human blood collected on surface snow is possible using all three collection methods tested. [ABSTRACT FROM AUTHOR]

• Providing a newly exploited trace DNA extraction platform based on magnetic bead-based method. • Establishing an automatic and efficient detection system for trace DNA. • The fingerprint materials were successfully dissected in the self-developed automatic detection system. The analysis of trace DNA is a crucial component in forensic applications. Biological materials containing low-level DNA collected at crime scenes, such as fingerprints, can be valuable as evidence. Automatic detection of biological samples has been largely embraced in forensic applications to meet the increasing throughput requirements. However, the amount of DNA automatically retrieved from trace evidence often tends to be small and unstable, ultimately resulting in poor detection of DNA profiles. Thus, in this work, we introduced a robust DNA extraction and purification platform named Bionewtech® BN3200 (Bionewtech®, Shanghai, China) with the goal of constructing a rapid automatic detection system for trace DNA. The establishment of automatic detection system for trace DNA mainly encompassed two parts: assessing the sensitivity of automatic extraction platform and screening the optimal short tandem repeat (STR) typing kit. The sensitivity of Bionewtech® BN3200 platform based on Ultra-sensitive DNA Extraction kit was initially estimated, demonstrating that this extraction platform might contain large potential in the trace DNA extraction. For the amplification part, three sets of commercial multiplex STR typing kits were selected as candidates, and the amplified products were further genotyped on the Applied Biosystems 3500xl Genetic Analyzer. After comparation, SiFa™ 23 Plex Kit was determined as the most suitable amplification system for trace DNA. Eventually, the newly exploited trace DNA detection system was successfully implemented in the detection of fingerprints derived from glass surfaces with the five-seconds contact time. As a result, the DNA recovered from the fingerprints fluctuated approximately from 57.60 pg to 18.05 ng, in addition, over 70% of the total STR loci were detected in 75% of the fingerprint samples. [ABSTRACT FROM AUTHOR]

• This work presents a discussion of digital evidence and the crime scene. • The concept of devices as 'digital witnesses' is discussed. • Digital investigative opportunities are examined in order to support first responders. • Approaches to scene-processing are debated in regards to digital evidence. Many criminal investigations maintain an element of digital evidence, where it is the role of the first responder in many cases to both identify its presence at any crime scene, and assess its worth. Whilst in some instances the existence and role of a digital device at-scene may be obvious, in others, the first responder will be required to evaluate whether any 'digital opportunities' exist which could support their inquiry, and if so, where these are. This work discusses the potential presence of digital evidence at crime scenes, approaches to identifying it and the contexts in which it may exist, focusing on the investigative opportunities that devices may offer. The concept of digital devices acting as 'digital witnesses' is proposed, followed by an examination of potential 'digital crime scene' scenarios and strategies for processing them. [ABSTRACT FROM AUTHOR]

• Lack of research in crime scene quality assurance has disadvantaged the field. • No unified understanding of competence or quality exists in crime scene practice. • ISO standards alone are inadequate to address scene-specific quality assurance frailties. • Organisational oversight models fail to ensure individual practitioner competence. • Jurisdiction-wide policy implementation through compellability is the way forward. Quality assurance in crime scene practice is an underdeveloped and underexamined field despite the cruciality attributed to scene work in achieving criminal justice goals. Formulation of robust strategies has been a shortcoming of oversight bodies, with a marked history of failure to address scene-specific requirements. This paper explores quality assurance mechanisms in the United Kingdom (UK) in order to uncover the longstanding status quo, and sustained challenges facing quality control regimes both on an organisational and personal level. Recommendations on a change in policy, implementation and philosophy are examined to assist with the formulation of effective quality assurance schemes in crime scene practice and align it closer to its laboratory counterparts. [ABSTRACT FROM AUTHOR]

• SfM photogrammetry can be applied for recovery of 3D footwear impressions. • Workflow and main sources of error are outlined. • Protocol for determining precision set out that can be used by any practitioner. • Range of examples and cases studies are presented. • Future research agenda to aid application in practice is established. The recovery of three-dimensional footwear impressions at crime scenes can be a challenge but can also yield important investigative data. Traditional methods involve casting 3D impressions but these methods have limitations: the trace is usually destroyed during capture; the process can be time consuming, with a risk of failure; and the resultant cast is bulky and therefore difficult to share and store. The use of Structure from Motion (SfM) photogrammetry has been used widely to capture fossil footprints in the geological record and while there is a small body of work advocating its use in forensic practice the full potential of this technique has yet to be realised in an operational context. The availability of affordable software is one limiting factor and here we report the availability of a bespoke freeware for SfM recovery and subsequent analysis of for footwear evidence (DigTrace). Our aim here is not to provide a rigorous comparison of SfM methods to other recovery methods, but more to illustrate the potential while also documenting the typical workflows and potential errors associated with an SfM based approach. By doing so we hope to encourage further research, experimentation and ultimately adoption by practitioners. [ABSTRACT FROM AUTHOR]

• An assessment of the relative rarity of the characteristics of glass. • A Dirichlet process mixture model to model glass refractive index was developed. • A continuous approach that can be implemented in a likelihood ratio framework. Glass is a common type of physical evidence in forensic science. Broken glass recovered from a suspect may have similar physical characteristics to glass collected at a crime scene and therefore can be used as evidence. Statistical treatment of this evidence involves computing a measure of the weight of evidence. This may be done in a Bayesian framework that incorporates information from the circumstances of the crime. One of the most crucial quantities in this calculation is the assessment of the relative rarity of the characteristics of the glass, essentially the probability distribution used to model the physical characteristics of recovered glass. Typical characteristics used in casework are the elemental composition of glass and the refractive index measurement. There is a considerable body of scientific literature devoted to the modelling of this information. For example a kernel density estimation has been used to model the background population of glass based on the refractive index measurement and a multivariate Gaussian finite mixture model has been used to model the elemental composition of glass. In this paper, we present an alternative approach, the Dirichlet Process Mixture Model, to model the glass refractive index measurement in a Bayesian methodology. A key advantage is that using this method allows us to model the probability density distribution of refractive index measurements in a more flexible way. [ABSTRACT FROM AUTHOR]

This study proposes a comprehensive, scalable guide which police forces may use to advertise and recruit crime scene staff on a universal standard, as opposed to setting force-specific requirements. It also investigates the validity of staff descriptors such as 'examiner', 'SOCO', 'analyst' and 'investigator' and whether such classifications warrant continued existence. Using published crime scene job postings and internal human resource documentation from thirty-five (35) United Kingdom police forces, scene staff qualification requirements and their assigned responsibilities were collated. The main functions of scene practitioners were found to involve six (6) key aspects: (1) operational support; (2) police organisation and forensic intelligence support; (3) administrative support; (4) community support; (5) organisational support; and (6) investigative support. The study found a major misconception in the understanding of the roles and responsibilities of crime scene practitioners as merely evidence collectors with purely evidence-based functions. The data indicated that the duties were significantly more dynamic, requiring critical thinking. Forces consistently emphasized the need for an ability to adapt to unknown scenarios, react with an open mind and problem-solve using reasoning and thought. Scene staff were expected to be victim based, their approach geared towards assisting victims to cope with crime, advising them as to the next steps forward, and consoling witnesses. Key discoveries were made about the role of scene staff as community support actors, and that role-fulfilment involved not just scientific knowledge but also legal and investigative comprehension. Insights were gained on the move towards professionalisation of crime scene staff and the associated obstacles. Evidence of widespread and jurisdiction-wide discrepancy in definitions, roles and responsibilities, police status (whether they were officers or civilians) and classification of scene practitioners under official staffing data, prompted recommendations on unification of standards and redefinition of staff roles and their vocational boundaries. [ABSTRACT FROM AUTHOR]

• Pollen analysis is useful in solving time- and location-related crimes. • Research activities are focused on improving light microscopy and optimising new methods. • Orthogonal analysis will improve the evidential weighting of forensic palynlogy. The forensic analysis of pollen involves the comparison of crime scene and reference pollen samples. Successful matches are frequently used to solve time- or location-related crimes. Despite its prospects in criminal investigation, forensic palynology is still underused in casework due to inherent shortcomings such as its limited evidential weighting, scarcity of skilled palynologists dedicated to forensic casework and the laborious nature of analytical procedures. To address these challenges, the current state-of-the-art in forensic palynology is transiting from the traditional light microscopic methods that dominated the early days of palynology to more contemporary approaches like Raman spectroscopy, stable isotope analysis and DNA metabarcoding. The major challenges of these methods, however, include a lack of optimisation to forensic expectations and the unavailability of robust databases to permit accurate data interpretation, and quests to resolve these problems constitute the theme of current research. While reiterating the usefulness of pollen analysis in criminal investigation, this report recommends orthogonal testing as a way of improving the evidential weighting of forensic palynology. [ABSTRACT FROM AUTHOR]

• Assessment of footprint contact area (FCA) from static and dynamic footprints and differences between them. • A total of 461 adults (230 males and 231 females) participated from north India. • No statistically significant differences observed between FCA of static and dynamic footprints. • Statistically significant sex differences found in both footprint types. • Implications of the study discussed in the analysis of footprints recovered from the crime scenes. When found at crime scenes, footprints may be evidentially valuable and can assist with the identity of a perpetrator based on their features and/or measurements. Footprints can be either static (made while standing) or dynamic (made while walking). While extensive research has been performed on the linear measurements obtained from static and dynamic footprints, research on the comparisons between the contact area of static and dynamic footprints in the forensic context are limited. The present study compares the contact area of static and dynamic bare footprints to determine if statistically significant differences exist between the two. Static and dynamic footprints were obtained from a sample of randomly-selected 461 Jatt Sikh adults (230 males and 231 females) of Indian origin between the ages of 19 and 32 years. The footprint contact area was calculated from each footprint (excluding the toes) using a PedoGRID® sheet. No statistically significant differences were observed between the contact area of static and dynamic footprints for each foot among males and females. However, statistically significant differences between both the sexes were found in the footprint contact areas of both footprint types. The right dynamic footprint contact area was found to be the most predictive measurement for classifying and estimating sex from a footprint's contact area. The study has implications in the analysis of footprints recovered from crime scenes. [ABSTRACT FROM AUTHOR]

• Artefact wiping and Trial obfuscation attacks are not noticed by forensic tools. • Compression bomb kills all tools while as Sparse file spares only OSForensics. • Encryption and Steganography attacks are identified by forensic tools but no evidence is retrieved. • TSK and FTK fail to locate Slack spaces, while as FTK also fails to locate HPA/DCO. This paper investigates whether computer forensic tools (CFTs) can extract complete and credible digital evidence from digital crime scenes in the presence of file system anti-forensic (AF) attacks. The study uses a well-established six stage forensic tool testing methodology based on black-box testing principles to carry out experiments that evaluate four leading CFTs for their potential to combat eleven different file system AF attacks. Results suggest that only a few AF attacks are identified by all the evaluated CFTs, while as most of the attacks considered by the study go unnoticed. These AF attacks exploit basic file system features, can be executed using simple tools, and even attack CFTs to accomplish their task. These results imply that evidences collected by CFTs in digital investigations are not complete and credible in the presence of AF attacks. The study suggests that practitioners and academicians should not absolutely rely on CFTs for evidence extraction from a digital crime scene, highlights the implications of doing so, and makes many recommendations in this regard. The study also points towards immediate and aggressive research efforts that are required in the area of computer forensics to address the pitfalls of CFTs. [ABSTRACT FROM AUTHOR]

• Improved STR profiles are obtained from 9 mm ammunition using a direct lysis method. • Successful STR profiling was achieved from both fired and unfired 9 mm cartridges. • For most samples the major profile observed matched the known handler. • 56% of profiles obtained from the direct lysis method produced LRs >1 million. Cartridge cases are often recovered from crime scenes involving firearms and, in the United Kingdom (where gun possession is strictly controlled), these are commonly from 9 mm calibre ammunition. The ability to obtain informative DNA profiles from touch DNA on recovered cartridges could have a significant impact on the investigation of that type of offence. However, this avenue may not be routinely considered as investigators in the UK have historically had a low expectation of obtaining useful DNA profiles. This stance may not be unreasonable given that (a) only trace amounts of DNA are likely to have been transferred onto the cartridge cases through handling; and (b) when the cartridge is spent, the potential deterioration of that DNA caused by the act of discharging the weapon. We introduce a novel semi-automatable method using direct lysis for the recovery of DNA from ammunition and compare it with a traditional double-swabbing method (using wet and dry swabs). DNA profiling of the DNA recovered using both methods was carried out using the ESI17 FAST STR system (Promega). This demonstrated a significant increase in DNA recovery using the direct lysis approach, and correspondingly improved STR results. We also investigated the effect on the recovery and profiling of DNA from fired, and unfired, 9 mm cartridges using the direct lysis technique. These results demonstrate that DNA suitable for STR analysis can still be recovered from fired ammunition with only slightly reduced yields compared to unfired ammunition. In these experiments, the handler of the ammunition was most commonly either the sole contributor or the major contributor to the recovered DNA profile. [ABSTRACT FROM AUTHOR]

• The study introduces 3D data capture to the analysis of insoles in a forensic context. • The study compares three different modes of data capture when using the Gunn methods. • Five of the six measurements of the Gunn method differed significantly between the three modes. • Further investigations need to be conducted on the use of 3D scanners to Forensic Podiatry. Foot impression evidence recovered from crime scenes can be available in the form of barefoot prints, sock-clad footprints, or as impressions within footwear. In some cases, suspects leave their footwear at the scene of the crime, and the insoles from the footwear can be important in linking a person to the footwear. The application of 3D data-collecting technology is becoming more and more popular within forensic science and has been used to recover footwear impression evidence. The present study is a feasibility study to discover if 3D data capturing devices can be applied to insoles; to capture the footprint impression for measurement using the Gunn method (a method used in forensic podiatry casework). Three different methods of data capture were conducted; Adobe Photoshop, MeshLab, and calipers used directly on the insole. Paired t-tests and Intraclass Correlation Coefficient (ICC) were conducted for all three data capture methods. Seven measurements used in this study were significantly different across all three methods. ICC scores were moderate to excellent for the Photoshop method, poor to good for the 3D method, and moderate to excellent for the Direct method. [ABSTRACT FROM AUTHOR]

Digital devices now play an important role in the lives of many in society. Whilst they are used predominantly for legitimate purposes, instances of digital crime are witnessed, where determining their usage is important to any criminal investigation. Typically, when determining who has used a digital device, digital forensic analysis is utilised, however, biological trace evidence or fingerprints residing on its surfaces may also be of value. This work provides a preliminary study which examines the potential for fingerprint recovery from computer peripherals, namely keyboards and mice. Our implementation methodology is outlined, and results discussed which indicate that print recovery is possible. Findings are intended to support those operating at-scene in an evidence collection capacity. [ABSTRACT FROM AUTHOR]

• Results demonstrate that recovery of footwear impressions from graves is feasible. • Higher quality of recovered footwear marks when covered with clothing. • Depth has an impact on recovery. Footwear marks are one of the most frequently encountered evidence types recovered from a crime scene and can provide valuable scene intelligence regarding potential suspects. It has been acknowledged that impressions of footwear and tools can be recovered from graves, but previous studies have only focused on tool mark recovery. This has led to a lack of published information regarding footwear mark recovery from graves. It is therefore important to demonstrate whether the recovery of footwear marks is feasible and, if so, under what conditions this can be achieved. To address recovery, this study, placed 60 three dimensional (3D) impressions of footwear marks within 60 simulated graves. This was done to assess time (1, 2, 4 months) and at known depths (20, 30, 40 cm). The footwear marks within the graves were covered with clothing or left uncovered. The shoe's design patterns were grouped and counted in a photographic comparison between the 3D footwear impressions, placed within the test-pits, and any recovered impressions. A grading system was adapted by the authors to score the quality of footwear impressions observed during recovery. The results demonstrate that the preservation and recovery of footwear impressions from graves is feasible. The simulated graves covered with clothing showed better preservation of footwear impressions, but there was no clear evidence that time or depth had an effect. The authors note that careful consideration and vigilant excavation skills are needed when excavating graves which may bear potential footwear marks, as their recovery will lead to an increased amount of intelligence that can link suspects to homicide scenes. [ABSTRACT FROM AUTHOR]

• Analysis of the prevalence of the ghosting phenomenon in dynamic (walking) footprints. was performed. • A direct visual examination of each footprint was done along with examination using software. • 136 dynamic footprints from 68 volunteers were collected and analyzed. • Ghosting was present on at least one location in all dynamic footprints. • The highest prevalence of ghosting occurred at the tip of the great toe, followed by the. second digit and the heel. Ghosting is a phenomenon that has been identified in dynamic (walking) footprints. There is sparse research on the occurrence of ghosting; however, due to the forensic value of footprints and their use in other scientific fields, the phenomenon of ghosting warrants further study. Ghosting can be used to determine if a footprint is static (standing) or dynamic, which can help forensic investigators create a sequence of events at a crime scene. Furthermore, this can help in footprint comparisons from this determination, as "like versus like" comparisons of dynamic or static footprints can be made. The purpose of this research was to determine the prevalence and locations of the ghosting phenomena in dynamic footprints. 136 dynamic footprints from 68 volunteers were collected using an inkless collection system. Each footprint was visually inspected for ghosting as well as examined using software. Ghosting was present on at least one location in all footprints. The highest prevalence occurred at the tip of the great toe, followed by the second digit and the heel. To a lesser extent, ghosting appeared at the tips of the other three digits. Ghosting often occurred at two or more areas in a given footprint. [ABSTRACT FROM AUTHOR]

• Virtual reality is an emerging technology with applications in teaching & learning. • A bespoke virtual reality app was used for teaching crime scene investigation skills • Our application supports learning and is enjoyable, cost-effective and accessible. • Virtual reality will add greater breadth of experience to forensic science courses. Simulated crime scene investigation is an essential component of forensic science education, but its implementation is costly and poses challenges to accessibility; offering personal investigations in higher education scenarios is often impossible. Virtual reality (VR) is an emerging technology which offers exciting prospects for teaching and learning, especially for imparting practical skills. We document here a multidisciplinary experimental study in which a bespoke VR crime scene app was designed and implemented, after which it was tested by both undergraduate student and staff/postgraduate student cohorts. Through both qualitative and quantitative analyses, we demonstrate that VR applications support learning of practical crime scene processing skills. VR-based practical sessions have the potential to add value to forensic science courses, through offering cost-effective practical experience, the ability to work in isolation and in a variety of different scenarios. Both user groups reported high levels of satisfaction with using the app and reports of adverse effects (motion sickness) were minimal. With reference to user feedback, we proceed to evaluate the scalability and development challenges associated with large-scale implementation of VR as an adjunct to forensic science education. [ABSTRACT FROM AUTHOR]

• The PowerPlex® Fusion DNA amplification kit was assessed for use with degraded DNA samples. • Damage was induced via UV exposure in the lab and naturally. • Kit performance was evaluated based on the obtained peak heights post damage. • Compared to non-damaged the damaged samples provided increased usable results. • Possible reasons for this are discussed. DNA samples collected at crime scenes are often degraded so this research focused on the ability of the Promega PowerPlex® Fusion 5C amplification kit to type both naturally and artificially degraded DNA. DNA was degraded naturally by placing equal volumes of blood on white fabric that was stored either inside, outside in a shaded area, or outside in direct sunlight. Samples were then collected every 10 days for 60 days and the DNA extracted (QIAamp® DNA Investigator). Artificially degraded samples were created by exposing extracted DNA to either UV light or 95 °C heat for varying times. DNA was also degraded artificially by placing blood samples into a 50% bleach solution for varying times prior to extraction. Following sample treatment, standard forensic DNA analysis was performed including quantification (Investigator® Quantiplex) and amplification (PowerPlex® Fusion 5C). Separation and detection were performed on an ABI 3130 xl capillary electrophoresis unit and analysis was performed using GeneMapper ID v3.2.1. While the time and shade samples showed similar amounts of degradation, the samples exposed to direct sun showed more degradation. The artificially degraded samples showed more signs of degradation such as reduced overall peak height and peak height imbalance at heterozygous loci. There were also some cases where an allele that was known to be in the profile exhibited total dropout. Although there were some instances of both allelic dropout and heterozygote peak imbalance, PowerPlex® Fusion was able to reliably type degraded DNA as all alleles detected were consistent with the known donor profile. The results show that PowerPlex® Fusion is a robust kit capable of handling forensically challenged samples. [ABSTRACT FROM AUTHOR]

• Reconstructing scene temperature is a challenger in forensic entomological case work. • This study summarizes the state of the art in temperature reconstruction. • Generalized additive models allows a more accurate reconstruction than other models. • Temperature at the crime scene should be measured at least for three days. The reliable reconstruction of the temperature conditions at a crime scene is still a great challenge in forensic-entomological case work. Despite many published standards and guidelines for reconstructing temperature, and studies analysing the influence of various factors on the accuracy on such reconstructions, there are astonishingly many cases in the literature in which the temperature at the place of discovery is not reconstructed at all, i.e. the most common method is using the data of the nearest meteorological weather station without any correlation with on-site data. This study summarizes the state of the art in temperature reconstruction from an entomological point of view and compares the application of generalized additive models (GAMs) and linear regression on the basis of hypothetical death scenarios with various post mortem intervals (PMI) and measurement periods for the correlation between crime scene and weather station. We show that GAMs i.e. analysing the potential delay effect of temperature within a day, are the tools of choice because they give better, i.e. more accurate estimations than linear regression in 95,6% of all analysed cases regardless of the PMI, body discovery site and correlation period. Nevertheless, each case and crime scene is unique and therefore each entomological expertise should discuss the possible strengths and weaknesses of its temperature reconstruction. Even if temperature is not or cannot be reconstructed for various reasons, a comparison of on-site data with those of a meteorological weather station is the minimum forensic experts should do. [ABSTRACT FROM AUTHOR]

• The study compares bare footprints and foot impressions on insoles using a linear measurements. • Five of the seven measures on the bare footprints and the insole foot impressions did not differ. • CALC and A1 measures differed significantly between the bare footprints and foot impressions. • Potential implications in the forensic analysis of foot impression evidence on footwear insoles. Footwear may be found at crime scenes as physical evidence. Such footwear often has impression features of the wearer's foot on the insole of the shoe. Scientific research and literature have established that footprints are distinct. This study compares two-dimensional measurements on bare footprints to foot impressions on insoles to determine if significant differences or similarities exist. Dynamic footprints were collected from 51 donors using the Identicator® Inkless Shoe Print Model LE 25P system. Seven foot length and width measurements were taken based on the Reel linear measurement method. Footprint measurements between bare footprints and foot impressions on the insoles were compared. Only two differences (p > 0.05) were observed between the various bare footprint and insole foot impression measurements on the right and left side for most of the measurements, CALC (p < 0.001) and A1 (p = 0.04). Bare footprint and insole A5 measurements on the left side were also significantly different (p = 0.015). The results of the study have implications in the forensic analysis of foot impression evidence on insoles in footwear in assisting with identifying the wearer of said footwear. Situations may arise in the forensic context when comparing the foot impression on the insole of footwear to a suspect's bare footprint or a footprint from post-mortem remains. This study contributes to the scant literature available on the topic and to understanding the similarities and differences observed in the various linear measurements that may be utilized in the comparison process of footprint impressions on shoe insoles to bare footprints. [ABSTRACT FROM AUTHOR]

• End goal of crime scene reconstruction is to obtain as much information as possible. • Geomatic techniques allow scenes to be mapped and measured quickly and efficiently. • Produce visually pleasing outputs that generate accurate and reliable measurements. • To be used in conjunction with already established manual methods. • Not to be used on every scene but to the investigator's discretion. The purpose of this review paper is to highlight various geomatic techniques that crime scene reconstructionists or forensic practitioners can use to document different kinds of scenes, highlighting the advantages, disadvantages, and when best to use each technology. This paper explores geomatic techniques such as a total station, photogrammetry, laser scanners and structured light scanners and how they can be used to reconstruct crime scenes. The goal of this paper is not to discredit manual methods, as they are long standing and reliable, but instead to shed light on alternative methods that may produce equally or more accurate results with a more visually appealing final product. It is important for law enforcement and forensic professionals to understand the advantages and disadvantages of each technique, knowing when certain techniques should be used (and when they should not), and being able to revert to traditional methods if required. [ABSTRACT FROM AUTHOR]

Activity level evaluations, although still a major challenge for many disciplines, bring a wealth of possibilities for a more formal approach to the evaluation of interdisciplinary forensic evidence. This paper proposes a practical methodology for combining evidence from different disciplines within the likelihood ratio framework. Evidence schemes introduced in this paper make the process of combining evidence more insightful and intuitive thereby assisting experts in their interdisciplinairy evaluation and in explaining this process to the courts. When confronted with two opposing scenarios and multiple types of evidence, the likelihood ratio approach allows experts to combine this evidence in a probabilistic manner. Parts of the prosecution and defence scenarios for which forensic science is expected to be informative are identified. For these so called core elements, activity level propositions are formulated. Afterwards evidence schemes are introduced to assist the expert in combining the evidence in a logical manner. Two types of evidence relations are identified: serial and parallel evidence. Practical guidelines are given on how to deal with both types of evidence relations when combining the evidence. Unlabelled Image • Evidence schemes provide structure from crime scene to courtroom. • Complex scenarios are broken down into manageable core elements. • Evidence relations may be categorised as either serial or parallel. • Evidence schemes make combining evidence easy to understand. • Evidence schemes can be communicated to legal practitioners. [ABSTRACT FROM AUTHOR]

• Insects from a crime scene can be useful in the victim identification process. • Megaselia scalaris is an important colonizer of buried or indoor bodies. • 5 protocols were evaluated in order to optimize the gut content extraction. • Despite the small size the larval gut content was successfully extracted. • Full STR profiles were obtained using a minimum of a single larva. [ABSTRACT FROM AUTHOR]

Soil forensics utilizes extensive soil information to answer legal questions and test hypotheses. The main difficulty often is the determination of different variables from a small amount of soil sample collected on the suspect. We developed a sequential mineralogical and chemical analyses to assess a limited quantity of soil vestiges (0.5 g) from a suspect's vehicle (adhered to the outside rear-view mirror and to the left front fender) involved in a murder case and compared them with the surface samples found at the victim's body disposal site at the Graciosa Road, Paraná State, Brazil. All results affirm that the suspect's vehicle could have been in contact with the edge of the Graciosa Road, approximately the place where the victim's body was located. As a result of the soil analysis and comparison, the results support the likely contact of the suspect's vehicle with the crime scene. • From 0.5 g we obtained 22 quantitative variables. • Soil from suspect vehicle shares similarities with the victim's body location. • Data from sand fraction could excluded Curitiba and Colombo from the crime scene. • Sequential extractions were efficient when there was a limited soil sample. [ABSTRACT FROM AUTHOR]

In forensic intelligence-gathering, footprints have been shown to be valued evidence found at crime scenes. Forensic podiatrists and footprint examiners use a variety of techniques for measuring footprints for comparison of the crime scene evidence with the exemplar footprints. This study examines three different techniques of obtaining two-dimensional linear measurement data of dynamic bare footprints. Dynamic bare footprints were gathered from 50 students from a podiatric medical school using the Identicator® Inkless Shoe Print Model LE 25P system. After obtaining 100 bilateral footprints from the participants, the quantitative measurement data were collected by using three different measurement techniques: (i) a manual technique using a ruler (direct technique); (ii) an Adobe® Photoshop® technique; and (iii) a GIMP (GNU Image Manipulation Program) technique. The seven Reel linear measurement methodology was used for producing measurements using these three techniques. This study showed that all the mean bare footprint measurements on the right and left feet obtained using the direct technique were larger than those obtained using GIMP and Adobe® Photoshop® images. Differences were also observed in measurements produced using GIMP software and Photoshop images. However, the differences observed in the three techniques used for bare footprint measurements were not found to be statistically significant. The study concludes that there are no significant differences between the three measurement techniques when applied to two-dimensional bare footprints using the Reel method. It further concluded that any of these measurement techniques can be used when employing the Reel methodology for footprint analysis without significant difference. • Comparison of three techniques of obtaining measurement data of dynamic bare footprints. • A direct technique using a ruler; an Adobe® Photoshop® method; and a GIMP technique. • The Reel methodology of footprint analysis was used for producing measurements. • No significant differences were observed between the three measurement techniques. • Any of these techniques can be employed in the analysis of crime scene footprints. [ABSTRACT FROM AUTHOR]

What do policing leaders think and know of forensic science? Beyond crime scene investigators or detectives, how do police senior managers perceive the role, utility and limitations of forensic science? Very few empirical studies have addressed the issue. Forensic scientsts should be concerned about the perception that law enforcement senior managers have of their discipline for two reasons. First, strategic and financial decision-makers are obviously key players in the overall administration and provision of forensic science, either as a supervisor, money provider or as a customer. Second, literature has highlighted that other actors involved in forensic science underestimate the scope and possibilities offered by forensic science, hence limiting its exploitation and potential. Following interviews with 18 police senior managers from Quebec (Canada), this study shows that they generally restrict forensic science to a reactive discipline whose role and utility is to identify offenders and support the Court. This understanding of forensic science, like that of many others including a significant share of forensic scientists, differs from the perception of other police activities in modern law enforcement agencies where proactive action is sought. Considering these findings and the growing body of literature which calls for forensic science to connect more tightly with policing and security, we advocate a more extensive education of police leaders regarding the scope of forensic science. • This study aims to understand how police senior managers perceive forensic science. • 18 police senior managers in Quebec were interviewed about their crime scene units. • They mainly associate forensic science to the identification science paradigm. • Police leaders are rarely aware of the proactive usefulness of forensic intelligence. • Educating police senior managers on forensic science could improve policing. [ABSTRACT FROM AUTHOR]