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Abstract Analysis of hair for drugs is now a well established technique. It is being used increasingly in crime investigation but seldom in routine Coroner’s toxicology. Hair analysis is the only method of obtaining a reliable drug history for the weeks or months prior to death. Between 2004 and 2006 from the cases reported to HM Coroner, hair was submitted for analysis in addition to the routine specimens for 286 selected cases. These were all cases where drug use was thought to be involved in the death. The usefulness of the data from hair analysis was evaluated along with the data from the conventional samples. The types of cases were identified where hair analysis provided valuable supporting evidence. It was found that reliable information concerning long-term drug use was important in a wide range of cases including: – demonstrating a history of drug use or lack of it, demonstrating tolerance or lack of it, compliance with medication, death due to long-term cocaine use and its role in depression/suicide, sudden unexplained death, and excited delirium. The cases types are illustrated by reference to individual cases and the implications of the findings discussed. The study demonstrated that hair analysis can provide vital evidence in a wide range of cases reported to HM Coroner. This evidence can be invaluable to the pathologist, Coroner, and the family of the deceased in understanding both the medical cause of death and the circumstances surrounding the death.

One way to determine the presence of a suspect on the scene of graffiti sprayed public territory, is by seeking the presence of aerosol paint droplets transferred to his clothing and accessories. Previous studies have evaluated the distribution of spray paint droplets in closed space, on clothing, and its persistence following washing. Yet, due to the difficulty in observing and counting them under a stereomicroscope, the previous studies had to limit the tests conducted and limit the amount of data collected. In this paper, we perform simulations of spraying using a fluorescent paint and a computer-automated extraction of features and counting of the droplets. With these tools we were able to perform many different tests in a relatively small amount of time and gather data about the density, distribution, and size of the droplets transferred. We discuss the obtained results and hypothesize that such evaluations of the transferred droplets would permit to distinguish between different scenarios at an activity level, such as the presence on the scene as a simple witness or bystander, versus the illicit action of spraying a graffiti or a tag.

The suicide rate in the United States is consistently higher in the elderly (>-65 years) than among younger cohorts, reaching approx 5500 deaths in 2002. In this article, we present a 10-year (1993–2002) retrospective review of 348 Kentucky medical examiner cases ascribed to suicide between 65 and 96 years. Most victims were males (86.8%) and Caucasian (98.9%). The predominant cause of death was firearm injury (80.7%), followed by hanging (4.9%) and overdose (4.3%). The pervasiveness of elderly suicide by firearm requires a multidisciplinary approach to the recognition of indicators and the development of strategies for treatment and prevention of suicide in at-risk elders.

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.

Pulmonary fat embolism is widely recognised in forensic pathology. Pulmonary fat embolism requires mobilisation of free fat, entry of free fat into the circulation and lodging of fat globules in fine venous capillaries. This paradigm of fat embolisation has been used to support the evidence of antemortem fat depot disruption when the presence of intravascular fat is confirmed at autopsy. However, sporadic reports of intravascular fat in various medical conditions, which contradict the above mechanism, have opened questions about the alternative pathogenesis. In this study, 65 cases of sudden deaths were examined for the presence of pulmonary intravascular fat (PIF) by osmium impregnation. Cases were selected based on the criteria that were designed to eliminate the possible confounding effect from medical intervention or postmortem changes. Slides were graded based on their ease of search and only the fat droplets confined by the blood vessel or capillary wall were considered as a positive finding. The results show surprisingly high PIF incidences of varying degrees in all the categories of sudden deaths. Further study is needed to devise criteria for diagnosis of fatal fat embolism since the histological appearance of the high-grade PIF in natural sudden death may not be easily distinguishable from the traumatic fat embolism.

Summary. Background: To control for the confounding effect of maturation many researchers use secondary sex characteristics to compare individuals within and between genders. However, this assumption presumes that the timing and tempo of secondary sex characteristics is identical in both genders. Aim: The study investigated the timing and relationships between sexual and somatic maturation indices between and within genders. Subjects and methods: Eighty three boys and 75 girls, aged between 8 and 15 years at study entry, were measured every 6 months for 6 consecutive years. Sexual maturation was assessed through pubic hair, facial hair and axillary hair development in boys, and pubic hair development and menarcheal status in girls. Somatic maturation was assessed through age at peak height velocity (PHV). Results: Low to moderate correlations (r ¼ 0.30–0.55, p<0.05) existed between age of PHV and age of reaching each pubic hair stage. The majority of boys reached PHV in pubic hair stage 4 (79.2%). The majority of girls reached PHV in pubic hair stage 3 (42.5%) and pubic hair stage 4 (47.5%). Conclusion: Boys and girls differ in the timing and tempo of somatic and sexual maturity. Thus boys and girls should not be aligned on secondary sex characteristics when controlling for the confounding effects of maturity.

In many fields of toxicology, numbers are used as threshold values, e.g. as "acceptable daily intake values" resulting in maximum permissible concentrations in food or in animal feed by using "safety factors"; maximal admissible concentrations of toxic substances in the air at the workplace; cut-off values in analytical toxicology; limit values for biological specimens in the case of driving under the influence of drugs, guidance values for environmental specimens, etc. The philosophy behind these values must be well understood and they should only be applied to real cases by persons with enough toxicological background. The bad use of these numbers in toxicology can have dramatic consequences. Especially in regulatory toxicology their use should be made with great care. Moreover, tremendous improvements in analytical methodology, e.g. the decreasing of the limits of detection for many potentially toxic substances in recent years, should not end up in an overestimation of risks to humans. To avoid these abuses careful interpretations of analytical findings by qualified toxicologists are of paramount importance. The use and abuse of some of these threshold values will be outlined in several applications from analytical toxicology, risk assessment issues, forensic toxicology in post-mortem cases, as well as from the drugs and driving cases. Generally, if threshold values are considered as guidance values and not as the "absolute truth" in toxicology, they may be very useful in the interpretation of toxicology data.

A 38-year-old male was arrested 7 times over an 8-month period for driving under the influence (DUI) of drugs. In each incident, gamma-hydroxybutyrate (GHB) was determined to be the causative agent. A blood specimen was drawn between 1.5 and 2.5 h after first police contact in each arrest. GHB was analyzed by gas chromatography-mass spectrometry, following extraction from blood using ethyl acetate and subsequent derivatization using BSTFA/TMCS. Blood GHB concentrations ranged from 44 to 184 mg/L (N = 7, mean 100 mg/L, median 73 mg/L). Overall signs of impairment included erratic driving (severe lane travel, collisions, and near-collisions), slurred speech, disorientation, slow to react, shaking, agitation, unable to focus, poor coordination and balance, poor performance in field sobriety tests, somnolence, and unconsciousness. On only one occasion were other drugs present in the subject's blood (thiopental and diazepam), which may have contributed to the observed driving impairment. During several police interviews, the subject stated he was addicted to GHB and gamma-butyrolactone (GBL), and admitted to previously taking "RenewTrient", "Dream On", "V35", "fitness supplements", and/or "GBL". During the same period as his DUI arrests, the subject had been admitted at least six times to different hospitals for GHB/GBL intoxications.

Abstract In forensic death investigations, estimating the postmortem interval (PMI) is critical. An accurate PMI estimate increases the speed and accuracy of identifying the remains by narrowing the time frame in which the death occurred, thus reducing the pool of possible decedents. Cape Town, South Africa has a high level of unnatural death, and due to a burdened death investigation system, many remain unidentified. There has been a tendency to broadly apply quantitative models of decomposition across biogeographically unique circumstances. A prime example is the widespread application of the total body score (TBS)/accumulated degree day (ADD) model developed by Megyesi et al. (2005), later refined by Moffatt et al. (2016). However, the appropriateness of applying a single model to a wide range of locations with unique geography and climates remains in question. The aim of the study was to evaluate and compare the accuracy of Megyesi and Moffatt models for estimating PMI in Cape Town, South Africa. Using pig carcasses, Finaughty established baseline data on the rates and patterns of terrestrial decomposition in summer and winter in two different locations in a forensically significant area of Cape Town. Among the baseline data, Finaughty derived TBS values using the Megyesi criteria. The present study used these values to estimate the ADD per the Megyesi and Moffatt models, which would correspond to an estimated PMI. These estimated values were compared to actual ADD values. Estimates of ADD were inaccurate for both models in winter, and only partially in summer. The Moffatt model was more accurate in earlier decomposition stages, with the Megyesi model more accurate in later decomposition stages. These results indicate the Cape Town environments may contain factors that the two models do not consider, producing inaccurate PMI estimations at various TBS’ values. ADD does not depict the entire taphonomic story; the decomposition process appears to be too complex for universal modelling based on a single or narrow suite of variables. Seasonality was an important factor in determining the accuracy of the models, primarily resulting in underestimations of the true PMI values. These findings show the impracticality of applying models developed for- or in one region to any other and support the need to establish regionally-specific equations for estimating PMI in a forensic context. Alternatively, more complex models employing “big data” from a more comprehensive suite of variables which influence the rate and pattern of decay could be developed.