The abandonment of neonates in locations where discovery and survival is not intended is a global concern. These cases comprise non-viable foetuses and stillbirths (natural deaths), as well as abandoned live births (unnatural deaths); the latter having possible legal consequences. To describe the profile of abandoned neonates and obtain a global perspective of the post-mortem investigation in such cases, a systematic review of the literature on abandoned foetuses, concealed births and neonaticide was conducted. This revealed a paucity of research on the subject; only one published South African study and less than 30 studies from other parts of the world were obtained. While guidelines were available, a standard protocol for conducting the medico-legal investigation on abandoned neonates did not exist and the necessary extent of the investigation was debated. Furthermore, seemingly higher rates of abandoned neonates were observed in South Africa compared to elsewhere in the world, warranting investigation of these cases in a local setting. In an attempt to add to the data concerning abandoned neonates in South Africa, a case file review was carried out on abandoned live births, stillbirths and non-viable foetuses at Salt River Mortuary between 1 January 2012 and 31 December 2016 (n=249). Despite the majority of the cases being natural deaths, the cause of death frequently remained 'undetermined’ in these cases, often due to the presence of decomposition. Histological analyses were only performed in a small fraction of undetermined cases. Furthermore, the hypothesis that the prosecution rate of abandoned live births is extremely low was supported by this study, with only one case prosecuted in the 5- year period. For the remainder of the cases, the court status was given as either 'under investigation’ (47.8%) or 'case closed’ (47.8%). In the majority of the instances, the case was closed due to the unknown identity of the biological mother; however, DNA analyses were not performed in all of these cases. Overall, the data highlighted the need for the development and implementation of standard protocols, to ensure that cause of death and identification of the neonate can be established as far as possible.

In South Africa, there is a burden of unidentified deceased individuals in forensic mortuaries. When human remains are severely compromised, hard tissues may provide the only DNA source for identification. The QIAamp® DNA Investigator Kit is used in forensic laboratories worldwide, including in South Africa, to extract DNA for identification purposes. However, in local forensic casework, the DNA recovered from teeth is often of insufficient quantity and quality for generating a DNA profile. The phenol-chloroform DNA extraction method has demonstrated improved, yet inconsistent results, when used on hard tissues. Therefore, this study assessed DNA recovery from 52 human control teeth from three deceased individuals, using an optimised phenol-chloroform method. This method involved an overnight demineralisation, two additions of phenol/chloroform/isoamyl alcohol (25:24:1) and an ethanol precipitation, as used by the Australian Federal Police. Quantitative PCR (Quantifiler™ Trio DNA Quantification Kit) and DNA profiling (PowerPlex® ESI 16 System) were then used to assess DNA quantity and quality. Results were compared to those obtained from the same teeth but extracted using the QIAamp® DNA Investigator Kit. The phenol-chloroform method recovered DNA with significantly higher yields (p = 0.0454) and significantly less degradation (p < 0.0001). Despite this improvement, there was no significant difference in DNA profiling success. This study also did a preliminary analysis of other factors affecting results and suggested that premolars might be the best tooth type with regards to DNA quantity, quality and profiling. Furthermore, dental disease and jawbone had a significant impact on results from teeth. Lastly, the phenol-chloroform method was applied to six teeth from a marine decomposition case to assess its performance in a local forensic setting. DNA metrics were particularly poor in this casework example, highlighting how different forensic and control environments are and the need for further optimisation. Overall, this study supports the use of the phenol-chloroform method and has provided a preliminary suggestion of the best tooth type, jawbone and tooth condition for DNA analysis for forensic human identification.

Insects play an essential role in the resolution of medico-legal investigations. For various insects, like necrophagous flies, it is vital for their survival to find and inhabit a food source such as a decomposing body. This makes it possible to use these insects as evidence in medico-legal investigations. A crucial part of any medico-legal investigation is estimating the time that has elapsed since death, otherwise known as the post-mortem interval (PMI). The age of the oldest insects can provide the most precise estimation of the PMI. Flies undergo different stages of development. All the immature stages can be utilized as evidence at death scenes. Out of all the immature stages, pupae represent the oldest specimens, which makes them valuable in establishing a minimum time since death. Identification and aging of pupae is currently a challenging process since they all look similar in appearance. Few studies have been done on pupae for PMI estimation. This study aims to identify reliable morphological markers to aid in a more accurate age estimation of Lucilia sericata during the pupal stage. A total of 145 pupae were collected and examined for external morphological changes over time. Five pupae were collected at each time point. A total of six external morphological characteristics of the puparium and twenty external morphological characteristics of the pupae were initially examined. These characteristics were linked to age in accumulated degree hours (ADH), with the aim of creating a timeline that can aid in the estimation of pupal age. The pupal ADH ranges from the youngest being 6550 ADH and the oldest being 11300 ADH. The timelines identified several characteristics that develop during the early or late stages of development. Multiple linear regression analysis was performed to assess characteristics which were useful for estimating the age of the pupae (ADH) and develop a regression equation based on the data collected. The regression analysis identified 10 characteristics that are the most significant in aging pupae. They were the colour and shape of the labellum, leg length, leg width at full length, thoracic setae, facial setae, abdominal macrosetae, palp shape, genal setae and labrum colour. Some of these characteristics like the leg length and width and abdominal macrosetae did provide important time-breaks on their respective timelines. However, the development and the pigmentation of the compound eye also provided valuable time-breaks it's timeline.

Violence-related injuries are a major cause of mortality in the Western Cape (South Africa). Previous research has demonstrated an association between violent mortalities and drug use. Furthermore, long-term drug use has been shown to alter behaviour that may lead to violence. Hence, this study aimed to investigate the effect of long-term drug use on violence-related mortalities. Due to the drug retention properties of hair, it is the gold standard for demonstrating the historical pattern of drug use. Hair samples were collected from 92 violent death cases admitted to Salt River Mortuary (South Africa). A qualitative toxicological analysis was performed in 90 hair samples using a SCIEX X500R QTOF. Variables pertaining to the colour and length of the hairs were recorded. The majority of the hair samples were black (n=79), while others were black and white (n=5), greyish (n=3), light grey and reddish brown (n=1) and strong brown hair (n=1). Various toxicologically relevant substances were detected in 74 cases (82.2 %) in which a total of 54 different substances were detected in hair samples. Acetaminophen was the most prominent licit substance (47%) detected, followed by caffeine (18.9%) and diphenhydramine (12%). Methamphetamine was the most common illicit detected substance (54%), followed by methaqualone (43%). Segmented hair samples showed historical use in 81.2 % of cases. These results show that hair can be used as a supplementary sample during toxicological investigation in violent fatalities in the local context.