Applicability of the Madymo Pedestrian Model for forensic fall analysis.

Forensic reconstruction and scenario evaluation are crucial in investigations of suspicious deaths related to falls from a height. In such cases, distinguishing between accidental falls, being pushed or jumping is an important but difficult task, since objective methods to do so are currently lacking. This paper explores the possibility of repurposing a passive rigid body model of a human from commercially available crash simulation software for forensic reconstruction and scenario evaluation of humans dropping from heights. To use this approach, a prerequisite is that the human body model can produce realistic movements compared to those of a real human, given similar environmental conditions. Therefore, this study assessed the validity of the commercially available Simcenter Madymo Pedestrian Model (MPM) for simulating human fall movements. Experimental kinematic and kinetic data was collected from nine participants, who dropped from a height in three different ways: passively tilting over, getting pushed, and jumping. Next, the performance of the MPM in reproducing the kinematics of the experimental falls was assessed by comparing the orientation of the body 0.3 s after platform release. The results show that the MPM currently does not consistently reproduce the experimentally recorded falling movements across multiple falling conditions and outcome measures. The MPM must therefore be adapted if to be used for forensic reconstruction and scenario evaluation, for example by implementing active movement.

Digital reconstruction of fragmented tooth remains in forensic context.

Forensic odontology majorly focuses on the identification of victims through the analyses of oral and para-oral structures. Exposure to high temperatures and trauma can occur in mass disasters and may lead to the fracturing and fragmentation of teeth. These fragments may become very fragile and easily damaged while handling. Conventional methodologies such as the use of transparent nail polish, hair spray, cyanoacrylate or adhesives have been used to stabilize the fragmented pieces. This study introduces a new and innovative digital technique that utilizes three-dimensional surface scanning (3DSS) and rapid prototyping techniques to reconstruct fractured portions of the teeth. The results of qualitative congruency analysis suggest that over all variance of morphological error (0.0526 ± 0.05) mm. These results imply that the reconstructed 3D model can be used for various morphometric analyses.

Virtual Trauma Analysis of the Nineteenth-Century Severed Head of the Greek Outlaw Stavrou.

Human remains have been displayed in museums in Europe since many centuries for historical, cultural, and educational reasons. Of particular interest are skeletal remains and body parts that have suffered violent deaths and such remains often feature in Criminology Museums. Despite the well-acknowledged value of human remains in medical education, bioarchaeology, and research, the display of human remains still raises ethical considerations ranging in severity depending on the cultural substrate and legal framework of each country. Recent developments in medical imaging and visualisation are offering an alternative way. Taking into account the emerging issues regarding exhibition and handling of human remains, this research project aims to use virtual methods to reconstruct the circumstances of the death of a nineteenth-century outlaw comprising one of the human exhibits at the Criminology Museum of Athens in Greece.For the purpose of the project, the severed head of the outlaw Stavrou was CT scanned, and the data were used to reconstruct and to evaluate the ballistic trauma sustained at the time of his death. From the scans, it was possible to determine the minimum number of shots, entrance and exit wounds, approximate calibre of the bullets, approximate distance from which they were fired, and general velocity of the round.Shots are fired from the lateral left and backside of the head and bullets exited from the right frontal and temporal area causing extensive damage to the right craniofacial region. The direction of the shots coming from the back and left suggests that Stavrou was more likely ambushed by gendarmerie squads and not shot in a fair fight which would have caused entry wounds in the anterior surface of the body. This is in agreement with historical evidence that placed him in gunfire with his fellow gang member Karapanos against a government squad. On the other hand, the possibility of being captured alive and executed cannot be rejected based only on wound ballistics.This work would be excellent supplementary material to the actual human exhibit for the accurate presentation of Stavrou's history at the Criminology Museum. In addition, it would allow the virtual exhibition of the material for historical and teaching purposes to museums and universities anywhere in Greece and along the globe, thus overcoming the obstacles of moving the actual remains.

Just another railway fatality.

We report on a 56-year-old male who was found dead on railroad tracks, equipped with overhead high-voltage power lines (15,000 V AC). Apparently, the body had been hit by a passing train and completely severed at the mid-abdominal level. Based on this apparently unequivocal finding, the police initially assumed a fatal railway accident or suicide. However, close examination of the deceased's clothes revealed heat damage to at least four overlying layers of clothing in different locations. The rubber soles of his heavy leather shoes showed small holes in blackened areas underneath the toes. Furthermore, both socks revealed tears and fabric defects with burnt rims, again most prominent in the area of the toes. Skin burns, consistent with electric burns, and blistering were detected on the deceased's hands and feet. A broken fishing rod was found in the proximity. On autopsy, multiple injuries caused by severe blunt force with subsequent skull fracture and brain laceration as well as multiple injuries to the spinal column and rib fractures were found and visceral organs displayed multiple lacerations. However, the lack of relevant hematomas argues that these injuries were inflicted postmortem. Histological examination confirmed the presence of electric burns from electrocution. Based on the results of the forensic-pathological examination and additional investigations carried out at the scene of death, we could demonstrate that this highly unusual death was caused by an electrocution after contact of the fishing rod with the high-voltage power line and not by overrunning by the train.

Persistence of transferred fragrance on fabrics for forensic reconstruction applications.

It has recently been established that volatile organic compounds (VOCs) successfully transfer between clothing even with a short contact of 10 s, highlighting the potential to use VOCs in forensic reconstruction scenarios, such as sexual assault cases. The mid and low volatility compounds transferred in greater amounts than high volatility compounds. This study presents empirical data addressing the persistence of transferred VOCs on clothing for the first time. A series of experiments were carried out to determine the persistence of VOCs on clothing for time periods of up 4 weeks, on natural and synthetic fibres, and at three different environmental temperatures. The data indicate that the highest VOC amounts are generally obtained for shorter persistence times of up to 1 d. Whilst high volatility compounds were not recovered in sufficient amounts to allow quantification, the four other transferred VOCs were successfully quantified for persistence times of up to 4 weeks. The persistence for mid-volatility compounds follows decay curve trends in line with those previously obtained for fibres, glass and pollen. When comparing the persistence of VOCs on a natural and a synthetic fibre, for a persistence time of 1 h, the transferred VOCs were retained on a natural fibre in higher amounts than on a synthetic fibre. However, for longer persistence times the concentration of VOCs was similar between the two fabrics. Lastly, lower environmental temperatures resulted in higher recoveries for most VOCs, especially for short persistence times. These findings demonstrate that optimal recovery of VOCs from clothing occurs when the fabric is kept at cooler temperatures and analysed soon after the fragrance transfer occurred, although VOC recovery was possible at higher temperatures and after longer persistence times. Given the transfer and persistence characteristics of VOCs from fragrance, there is potential for fragrance to be used as a form of trace in forensic reconstruction approaches.

Fragrance transfer between fabrics for forensic reconstruction applications.

Sexual assault is a serious crime that often has low conviction rates. Recent literature has demonstrated that there is potential for fragrances to be valuable in forensic reconstructions where there has been contact between individuals. However, developing appropriate evidence bases for understanding the nature of fragrance transfer in these contexts is needed. This article presents three experiments that address the transfer process of fragrances that have been transferred from a primary piece of fabric onto a secondary piece of fabric, in a manner that could occur during an assault. The three variables studied were the ageing time of the fragrances on the first fabric prior to transfer, the contact time between the two fabrics, and lastly the fabric type (of the primary material and the recipient material). The transfer was evaluated using a validated solid phase micro-extraction gas chromatography-mass spectrometry (SPME GC-MS) method. The findings demonstrated that all three variables had an impact on the transfer of fragrances between clothing fabrics. Generally, lower volatility compounds were transferred and recovered in larger amounts than higher volatility compounds. All fragrance compounds were successfully recovered from a secondary piece of fabric even when the contact time was as short as 10 s, and even when the perfume was aged on the primary fabric for as long as 48 h. The nature of the fragrance transfer also depended on the fabric type, so that a clear discrimination was observed between the fragrance transfer that occurred onto a natural fabric (cotton) and onto a synthetic fabric (polyester).

Journey history reconstruction from the soils and sediments on footwear: An empirical approach.

The value of environmental evidence for reconstructing journey histories has significant potential given the high transferability of sediments and the interaction of footwear with the ground. The importance of empirical evidence bases to underpin the collection, analysis, interpretation and presentation of forensic trace materials is increasingly acknowledged. This paper presents two experimental studies designed to address the transfer and persistence of sediments on the soles of footwear in forensically relevant scenarios, by means of quartz grain surface texture analysis, a technique which has been demonstrated to be able to distinguish between samples of mixed provenance. It was identified that there is a consistent trend of transfer and persistence of sediments from hypothetical pre-, syn- and post-crime event locations across the sole of the shoe, with sediments from 'older' locations likely to be retained in small proportions. Furthermore, the arch of the shoe (the area of lowest foot pressure distribution) typically (but not exclusively) retained the highest proportion of grain types from previous locations including the crime scene. A lack of chronological layering of the retained sediments was observed indicating that techniques that can identify the components of mixed provenance samples are important for analysing footwear sediment samples. It was also identified that the type of footwear appeared to have an influence on what particles were retained, with high relief soles that incorporate recessed areas being more likely to retain sediments transferred from 'older' locations from the journey history. In addition, the inners of footwear were found to retain sediments from multiple locations from the journey history that are less susceptible to differential loss in comparison to the outer sole. These findings provide important data that can form the basis for the effective collection, analysis and interpretation of sediments recovered from both the outer soles and inners of footwear, building on the findings of previously published studies. These data offer insights that enable inferences to be made about mixed source sediments that are identified on footwear in casework, and provide the beginnings of an empirical basis for assessing the significance of such sediment particles for a specific forensic reconstruction.

Forensic science needs both the 'hedgehog' and the 'fox'.

Forensic science faces many challenges, some high profile and others that are less visible. It is argued that a holistic understanding of the complex matrix of forensic science is critical to robust and transparent forensic reconstruction approaches. This paper explores the value of incorporating the contrasting approaches to complexity of the 'hedgehog' and the 'fox', by illustrating their comparative strengths. The value of such collaboration in the context of a holistic understanding of the complex interactions that exist within forensic science, offers insights for developing approaches that can be taken to address the visible and less visible challenges at their root cause.

Preliminary development of a bleeding layer to assess the effect of a ballistic impact on textile damage.

When a person is shot, they are generally wearing clothing which will be damaged by the perforation of the bullet. There are relatively few reports of such textile damage in the literature and the effect of blood on the textile damage observed is not reported. The appearance of textile damage caused by bullet impacts is further compounded by the diverse nature of (i) fabrics used in apparel and (ii) ammunition types. In this work, the effect of blood on textile damage due to ballistic impact was investigated by the development of a specimen that incorporated blood. The specimens were impacted with two types of pistol ammunition that are commonly available (i) 9mm Luger HP (8.03g; Federal Premium® Law Enforcement; jacketed hollow-point) and (ii) .357 Magnum (10.24g; Express® Pistol and Revolver; Remington, R357M3, flat-nose soft-point). The resulting textile damage was compared to that in specimens without a bleeding layer. The interaction of blood with textile damage caused by a bullet-impact affected the appearance of the textile damage and resulted in the dispersion of the bullet wipe. These results are important in the content of evidence examined by a textile damage assessor compared to what might be seen in a typical re-creation event in a laboratory. The use of a bleeding layer in textile damage investigations due to ballistic impact resulted in a more realistic scenario.

Conceptualising forensic science and forensic reconstruction. Part II: The critical interaction between research, policy/law and practice.

This paper builds on the FoRTE conceptual model presented in part I to address the forms of knowledge that are integral to the four components of the model. Articulating the different forms of knowledge within effective forensic reconstructions is valuable. It enables a nuanced approach to the development and use of evidence bases to underpin decision-making at every stage of a forensic reconstruction by enabling transparency in the reporting of inferences. It also enables appropriate methods to be developed to ensure quality and validity. It is recognised that the domains of practice, research, and policy/law intersect to form the nexus where forensic science is situated. Each domain has a distinctive infrastructure that influences the production and application of different forms of knowledge in forensic science. The channels that can enable the interaction between these domains, enhance the impact of research in theory and practice, increase access to research findings, and support quality are presented. The particular strengths within the different domains to deliver problem solving forensic reconstructions are thereby identified and articulated. It is argued that a conceptual understanding of forensic reconstruction that draws on the full range of both explicit and tacit forms of knowledge, and incorporates the strengths of the different domains pertinent to forensic science, offers a pathway to harness the full value of trace evidence for context sensitive, problem-solving forensic applications.

Conceptualising forensic science and forensic reconstruction. Part I: A conceptual model.

There has been a call for forensic science to actively return to the approach of scientific endeavour. The importance of incorporating an awareness of the requirements of the law in its broadest sense, and embedding research into both practice and policy within forensic science, is arguably critical to achieving such an endeavour. This paper presents a conceptual model (FoRTE) that outlines the holistic nature of trace evidence in the 'endeavour' of forensic reconstruction. This model offers insights into the different components intrinsic to transparent, reproducible and robust reconstructions in forensic science. The importance of situating evidence within the whole forensic science process (from crime scene to court), of developing evidence bases to underpin each stage, of frameworks that offer insights to the interaction of different lines of evidence, and the role of expertise in decision making are presented and their interactions identified. It is argued that such a conceptual model has value in identifying the future steps for harnessing the value of trace evidence in forensic reconstruction. It also highlights that there is a need to develop a nuanced approach to reconstructions that incorporates both empirical evidence bases and expertise. A conceptual understanding has the potential to ensure that the endeavour of forensic reconstruction has its roots in 'problem-solving' science, and can offer transparency and clarity in the conclusions and inferences drawn from trace evidence, thereby enabling the value of trace evidence to be realised in investigations and the courts.

An experimental study addressing the use of geoforensic analysis for the exploitation of improvised explosive devices (IEDs).

The use of geoforensic analysis in criminal investigations is continuing to develop, with the diversification of analytical techniques, many of which are semi-automated, facilitating prompt analysis of large sample sets at a relatively low cost. Whilst micro-scale geoforensic analysis has been shown to assist criminal investigations including homicide (Concheri et al., 2011 [1]), wildlife crime (Morgan et al., 2006 [2]), illicit drug distribution (Stanley, 1992 [3]), and burglary (Mildenhall, 2006 [4]), its application to the pressing international security threat posed by Improvised Explosive Devices (IEDs) is yet to be considered. This experimental study simulated an IED supply chain from the sourcing of raw materials through to device emplacement. Mineralogy, quartz grain surface texture analysis (QGSTA) and particle size analysis (PSA) were used to assess whether environmental materials were transferred and subsequently persisted on the different components of three pressure plate IEDs. The research also addressed whether these samples were comprised of material from single or multiple geographical provenances that represented supply chain activity nodes. The simulation demonstrated that material derived from multiple activity nodes, was transferred and persisted on device components. The results from the mineralogy and QGSTA illustrated the value these techniques offer for the analysis of mixed provenance samples. The results from the PSA, which produces a bulk signature of the sample, failed to distinguish multiple provenances. The study also considered how the environmental material recovered could be used to generate information regarding the geographical locations the device had been in contact with, in an intelligence style investigation, and demonstrated that geoforensic analysis has the potential to be of value to international counter-IED efforts. It is a tool that may be used to prevent the distribution of large quantities of devices, by aiding the identification of the geographical location of key activity nodes.

Forensic imaging for causal investigation of death.

A 63-year-old man was found in the street after overrun by a car. Postmortem CT revealed multiple bone fractures, but surprisingly all without any relevant hemorrhage which would have been expected under such circumstances. A round radiopaque formation was found in the duodenum, which was reminiscent of ingested tablets. The toxicological analysis revealed high concentrations of zopiclone and alcohol. By combining radiologic and forensic results, zopiclone and alcohol intoxication were concluded as the cause of death, followed by a postmortem overrun accident.

Forensic Imaging for Causal Investigation of Death

A 63-year-old man was found in the street after overrun by a car. Postmortem CT revealed multiple bone fractures, but surprisingly all without any relevant hemorrhage which would have been expected under such circumstances. A round radiopaque formation was found in the duodenum, which was reminiscent of ingested tablets. The toxicological analysis revealed high concentrations of zopiclone and alcohol. By combining radiologic and forensic results, zopiclone and alcohol intoxication were concluded as the cause of death, followed by a postmortem overrun accident.

Evaluación de los métodos de localización del punto pronasal para la reconstrucción facial forense / Evaluation of the pronasal point prediction methods for forensic facial reconstruction

La reconstrucción facial por escultura forense es un procedimiento que se utiliza en identificación Humana. Consiste en la colocación de un material modelable sobre el esqueleto óseo, respetando los grosores tisulares y la anatomía facial. Una de las principales dificultades de la técnica es la reproducción de estructuras de posición variable como los ojos, las orejas y la nariz. Se ha descrito que es posible reconstruir la nariz de manera confiable si se cuenta con el punto pronasal, es por esto que se han desarrollado diversas técnicas para la ubicación de este punto a partir de osamentas craneales. El propósito de este estudio es evaluar mediante radiografías laterales la exactitud de 4 métodos ampliamente utilizados para la ubicación del punto pronasal a partir de cráneos. Se utilizaron 34 radiografías tomadas en norma lateral con perfil blando visible, sobre los cuales se realizaron los trazados de perfil blando y duro (perfil de control). Se evaluaron los métodos de Gerásimov, krogman, Prokopec & Ubelaker y de George, determinándose las diferencias existentes en un eje de coordenadas (X, Y) con respecto al gold estándar (punto pronasal determinado en el perfil blando). Todos los métodos presentaron bajos niveles de exactitud, subestimando la proyección anterior de la nariz. De acuerdo a las medias el método de Prokopec & Ubelaker fue el más cercano al gold standard, con medias de 5,6 (DS 3,66) en X y 1,7 (DS 3,3) en Y, y mayores niveles de exactitud, los otros métodos evaluados fueron menos exactos y presentaron una alta dispersión. El uso de métodos de determinación del punto pronasal confiables y aplicables a nuestra población es fundamental para la correcta reconstrucción de la nariz.

Facial reconstruction for forensic sculpture is a procedure used in human identification. It consists of placing a mouldable material on the bone, respecting the soft tissue and facial anatomy. One of the main technical difficulties is the reproduction of structures of variable position as the eyes, ears and nose. It has been reported that the nose can be reconstructed reliably if you have pronasal point, that's why we have developed various techniques for the location of this point from the cranial bones. The purpose of this study is to evaluate by mean lateral cephalometric radiography the accuracy of four methods widely used for the location of the pronasal point from skulls. 34 lateral cephalometric radiography with soft-tissue facial profile taken under standardized conditions were used, on which tracings were made in hard and soft profile (control profile). Gerasimov, Krogman, Prokopec & Ubelaker and George methods were evaluated, determining the differences in a coordinate axis (X, Y) with respect to the gold standard (pronasal point given in the soft profile). All methods had low levels of accuracy, underestimating the anterior projection of the nose. According to the averages, the method of Prokopec & Ubelaker was the closest to the gold standard, with averages of 5.6 (SD 3.66) in X and 1.7 (SD 3.3) in Y, and higher levels of accuracy. The other methods tested were less accurate and had a high dispersion. The use of reliables and applicables methods for determining the pronasal point to our population are essential for the proper reconstruction of the nose.