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The location of covert graves is an important but challenging part of missing persons investigations. Although traditional search techniques, such as foot searches and cadaver dogs, have proved successful, the incorporation of higher technology methods, such as geophysical techniques, can be used to increase the chances of locating covert graves. This article will present a field method for the use of two geophysical techniques, including ground penetrating radar and electrical resistivity tomography, which can successfully locate covert graves in an Australian environment. If the soil and climate conditions permit, this technical protocol can be applied to other clandestine grave search sites as well. Ultimately, by increasing chances of locating the covert grave, and by extension the missing person, a successful judicial outcome can be achieved and highly sought after answers can be provided to the family. [ABSTRACT FROM AUTHOR]

Locating clandestine graves presents significant challenges to law enforcement agencies, necessitating the testing of grave detection techniques. This experimental study, conducted under Australian field conditions, assesses the effectiveness of time-lapse ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) in detecting pig burials as simulated forensic cases. The research addresses two key questions: (1) observability of graves using GPR and ERT, and (2) changes in geophysical responses with reference to changing climatic conditions. The principal novelty of this research is its Australian focus—this is the first time-lapse GPR and ERT study used to locate clandestine graves in Australia. The results reveal that both GPR and ERT can detect graves; however, ERT demonstrates greater suitability in homogeneous soil and anomalously wet climate conditions, with the detectability affected by grave depth. This project also found that resistivity values are likely influenced by soil moisture and decomposition fluids; however, these parameters were not directly measured in this study. Contrastingly, although GPR successfully achieved 2 m penetration in each survey, the site's undeveloped soil likely resulted in inconsistent detectability. The findings underscore the significance of site-specific factors when employing GPR and/or ERT for grave detection, including soil homogeneity, climate conditions, water percolation, and body decomposition state. These findings offer practical insights into each technique's utility as a search tool for missing persons, aiding law enforcement agencies with homicide cases involving covert graves. [ABSTRACT FROM AUTHOR]

Surveillance is ubiquitous in modern society, allowing continuous monitoring of areas that results in capturing criminal (or suspicious) activity as footage. This type of trace is usually examined, assessed and evaluated by a forensic examiner to ultimately help the court make inferences about who was on the footage. The purpose of this study was to develop an analytical model that ensures applicability of morphometric (both anthropometric and morphological) techniques for photo-comparative analyses of body and gait of individuals in CCTV images, and then to assign a likelihood ratio. This is the first paper of a series: This paper will contain feature extraction to observe repeatability procedures from a single observer, in turn, producing the frequency and distinctiveness of the feature set within the given population. To achieve this, an Australian population database of 383 subjects (stance) and 268 subjects (gait) from both sexes, all ages above 18 and ancestries was generated. Features were extracted, defined, and their rarity viewed among the developed database. Repeatability studies were completed in which stance and gait (static and dynamic) features contained low levels of repeatability error (0.2%–1.5 TEM%). For morphological examination, finger flexion and feet placement were observed to have high observer performance. [ABSTRACT FROM AUTHOR]

The changes that occur to the human body after death reflect a multitude of complex biological processes, which can be impacted by a collection of variables that are not yet fully understood. Typically, information is obtained through in-situ examination and/or 2D data collection, which may restrict the availability of data and prevent collection of valuable information. To address this gap, the aim of this paper is to present a protocol for 3D data collection of human decomposition in outdoor environments. The specific objectives include presenting an approach and framework using wildlife cameras and performing 3D observation of a decomposing body. The method includes the design and construction of a walk-in cage including five frames holding 31 cameras, installed at the Australian Facility for Taphonomic Experimental Research. Preliminary trials completed on one subject in Zurich and various objects provided promising results through the generation of a 3D model. Comparing the wildlife cameras 3D model with a high-quality 3D model showed only minor discrepancies. This approach will be used in a study designed to improve our understanding of the human decomposition process to ultimately assist investigators with PMI estimations and to help reconstruct the sequence of events and time of death. [ABSTRACT FROM AUTHOR]

Research in many forensic science fields commonly uses domestic pigs (Sus spp.) as proxies for human remains, due to their physiological and anatomical similarities, as well as being more readily available. Unfortunately, previous research, especially that which compares the decompositional process, has shown that pigs are not appropriate proxies for humans. To date, there has not been any published research that specifically addresses whether domestic pigs are adequate human proxies for the geophysical detection of clandestine graves. As such, the aim of this paper was to compare the geophysical responses of pig cadavers and human donor graves, in order to determine if pigs can indeed be used as adequate human proxies. To accomplish this, ground penetrating radar (GPR) and electrical resistivity tomography (ERT) responses on single and multiple pig cadaver graves were compared to single and multiple human donor graves, all of which are in known locations within the same geological environment. The results showed that under field conditions, both GPR and ERT were successful at observing human and pig burials, with no obvious differences between the detected geophysical responses. The results also showed that there were no differences in the geophysical responses of those who were clothed and unclothed. The similarity of the responses may reflect that the geophysical techniques can detect graves despite what their contents are. The study implications suggest that experimental studies in other soil and climate conditions can be easily replicated, benefiting law enforcement with missing persons cases. [ABSTRACT FROM AUTHOR]

Tattoos are secondary identifiers that can be used to provide a presumptive identity and provide information about a deceased individual to a case. Additional information may be available through the analysis of the visual presentation of tattoos. The aim of this study was to examine the morphological changes of tattoos during the decomposition of a human donor in an Australian environment. Using time-lapse cameras recording for 16 months, stills were extracted and tattoos were quantified using ImageJ. A full analysis was completed on three tattoos, while a fourth tattoo was partially analysed. The tattoos showed the most change in area during the bloat stage of decomposition, staying relatively constant in size for the remainder of the study. The detailed shape of the outlines showed the morphological effect of desiccation as part of decomposition and continued to change until the tattoo was no longer visible. Of the tattoos fully analysed, two became redundant as secondary identifiers on day 294, the other on day 333, all due to lack of visibility. This information is useful during investigations of unknown deceased persons; in this case, the stage of decomposition influenced the presentation of the tattoo. [ABSTRACT FROM AUTHOR]

Post-mortem movement relating to the disarticulation or positional change of entire limbs is relevant to a forensic investigator when examining a deceased person. Understanding that the position a body is found is not necessarily the way it was left changes the approach an examiner must take when investigating any death. This study quantified post-mortem movement of a human donor decomposing in an Australian environment over 16 months: 1) progressive measurement of the angles of joints; and 2) distance of separation between the articulating points of bones. ImageJ software was used to calculate angles and the distances between structures from time-lapse images. Movement was detected at all joints of the upper and lower limbs, occurring at all stages of decomposition across the study. Significant movement of the joints occurred as a result of bloat during the early stages of decomposition, and again during the advanced stages of decomposition as the soft tissue desiccated. Disarticulation was observed in the late stages of decomposition in all limbs and was not exclusive to short or long bones. Disarticulation also generated significant movement between skeletal structures in late decomposition. The results demonstrate that it is essential to consider post-mortem movement when investigating unexplained deaths. [ABSTRACT FROM AUTHOR]