Petechial Hemorrhages and Ethanol in Deaths from Intoxication

Petechiae in conjunctivae and in the palpebrae/skin of the eyelids are of particular interest for the forensic pathologist, because of their association with pressure on the neck. They have been described in the eyelids of intoxicated persons both in case reports and in text books of forensic pathology. We studied 590 deaths caused by intoxication, and 75 had petechiae either in the conjunctivae, the eyelids, or in both locations. We examined the influence of drugs and ethanol on the location of the petechial hemorrhages in these deaths. Deaths with ethanol in blood and in urine/vitreous humor more often had petechiae in both locations than those without. This association was statistically significant, independent of body position and livor mortis. No association between the location of petechiae, medicinal drugs, or narcotics was found. These results suggest that ethanol may contribute to the development of petechial hemorrhages in deaths from intoxication.     

Fluorescence Imaging of Posterior Spiracles from Second and Third Instars of Forensically Important Chrysomya rufifacies (Diptera: Calliphoridae),

Entomological protocols for aging blowfly (Diptera: Calliphoridae) larvae to estimate the time of colonization (TOC) are commonly used to assist in death investigations. While the methodologies for analyzing fly larvae differ, most rely on light microscopy, genetic analysis, or, more rarely, electron microscopy. This pilot study sought to improve resolution of larval stage in the forensically important blowfly Chrysomya rufifacies using high‐content fluorescence microscopy and biochemical measures of developmental marker proteins. We established fixation and mounting protocols, defined a set of measurable morphometric criteria and captured developmental transitions of 2nd instar to 3rd instar using both fluorescence microscopy and anti‐ecdysone receptor Western blot analysis. The data show that these instars can be distinguished on the basis of robust, nonbleaching, autofluorescence of larval posterior spiracles. High‐content imaging techniques using confocal microscopy, combined with morphometric and biochemical techniques, may therefore aid forensic entomologists in estimating TOC.     

'Your personality is the intervention': a grounded theory of mental health nurses’ beliefs about hope and experiences of fostering hope within a secure setting

Hope is an important factor in psychological resilience and change, and recovery from mental health difficulties. Recently, there has been an increased focus on recovery-oriented practice within forensic mental health settings. Several policies include calls for mental health practitioners to inspire hope for recovery in the individuals they work with. However, there is little suggestion of how to implement such recommendations in practice or research exploring how staff foster hope in forensic settings. This study used grounded theory to explore nurses’ perspectives and experiences of hope within a medium secure setting. A model was developed from the data that integrated nurses’ beliefs about hope, practices to develop service users’ hope and the emotional impact of this work. The nurses’ values played a significant role in their work to develop hope. Recommendations are made to help manage the emotional impact and address challenges unique to fostering hope within forensic settings.     

Status of Mandibular Third Molar Development as Evidence in Legal Age Threshold Cases

The completion of the third molar roots has played an important role in ascertaining whether individuals may be at or over a legal threshold of age, often taken as 18 years. This study demonstrates that root apex completion in the third molar is relatively uninformative regarding the threshold of age 18 years in a sample of 1184 males, where mean age‐of‐attainment of root apex completion for third mandibular molars is about 19.4 years. This paper also considers the legal age threshold problem for cases where the third mandibular molar is not completely formed, and outlines the use of parametric models and Bayes’ factors to evaluate dental evidence in statistically appropriate ways. It attempts to resolve confusion over age‐within‐stage versus age‐of‐attainment, likelihood ratios versus other diagnostic tests, and prior odds for a case versus the prior density for an age distribution.     

Alprazolam and Zolpidem in Skeletal Tissue of Decomposed Body Confirms Exposure

In several medico‐legal cases, bone samples analysis may provide the only source of toxicological information. This case study reports the analysis of a human bone specimen, belonging to a 46‐year‐old man, found 3 months after his death due to cervical–thoracic injuries in a motorcycle accident. Bone specimen was the only available material for toxicological analysis, among few skull hair and rotten skin. Analysis was performed by a newly developed and validated ultra‐high‐pressure liquid chromatography–mass spectrometry/mass spectrometry (UHPLC‐MS/MS) method, following simple and efficient sample pretreatment. The results were in accordance with the man's medical record: Alprazolam and zolpidem were found at 2.2 and 5.4 ng/g of bone, respectively. Both these drugs were prescribed to the deceased.     

An Evidence‐based Forensic Taxonomy of Windows Phone Dating Apps

Advances in technologies including development of smartphone features have contributed to the growth of mobile applications, including dating apps. However, online dating services can be misused. To support law enforcement investigations, a forensic taxonomy that provides a systematic classification of forensic artifacts from Windows Phone 8 (WP8) dating apps is presented in this study. The taxonomy has three categories, namely: Apps Categories, Artifacts Categories, and Data Partition Categories. This taxonomy is built based on the findings from a case study of 28 mobile dating apps, using mobile forensic tools. The dating app taxonomy can be used to inform future studies of dating and related apps, such as those from Android and iOS platforms.     

Can training improve eyewitness identification? The effect of internal feature focus on memory for faces

Evidence suggests that individuals rely on external features such as hair and face shape when processing and recognising unfamiliar faces. This is problematic in a forensic setting because hairstyle can be changed easily. In two studies we examined whether training individuals to focus more on the stable, internal features of the face (e.g. eyes, nose and mouth) and hence less on the changeable external features would improve identification accuracy. In Study 1, participants were instructed to focus on: (1) internal features, (2) external features, or (3) both internal and external features. Participants’ eye movements were monitored while they studied target faces, which they later tried to identify from an array that included the target with a changed appearance. In Study 2, participants were instructed to focus on: (1) internal features, (2) external features, or (3) given no instructions. Participants were required to identify target faces from line-ups, where they were presented either unchanged or with an altered hairstyle. Results suggested that training individuals to attend to internal features of unfamiliar faces may improve identification accuracy in the common situation where external features have changed between presentation and identification. However, internal feature focus may decrease identification accuracy when external features are unchanged.     

Quantification of human mitochondrial DNA using synthesized DNA standards

Successful mitochondrial DNA (mtDNA) forensic analysis depends on sufficient quantity and quality of mtDNA. A real-time quantitative PCR assay was developed to assess such characteristics in a DNA sample, which utilizes a duplex, synthetic DNA to ensure optimal quality assurance and quality control. The assay's 105-base pair target sequence facilitates amplification of degraded DNA and is minimally homologous to nonhuman mtDNA. The primers and probe hybridize to a region that has relatively few sequence polymorphisms. The assay can also identify the presence of PCR inhibitors and thus indicate the need for sample repurification. The results show that the assay provides information down to 10 copies and provides a dynamic range spanning seven orders of magnitude. Additional experiments demonstrated that as few as 300 mtDNA copies resulted in successful hypervariable region amplification, information that permits sample conservation and optimized downstream PCR testing. The assay described is rapid, reliable, and robust.     

Interrater reliability of Risk Matrix 2000/s

Actuarial risk assessment instruments for sexual offenders are often used in high-stakes decision making and therefore should be subject to stringent reliability and validity testing. Furthermore, those involved in the risk assessment of sexual offenders should be aware of the factors that may affect the reliability of these instruments. The present study examined the interrater reliability of the Risk Matrix 2000/s between one field rater and one independent rater with a sample of more than 100 sexual offenders. The results indicated good interrater reliability of the tool, although reliability varies from item to item. A number of factors were identified that seem to reduce the reliability of scoring. The present findings are strengthened by examining interrater reliability of the tool in the usual practitioner context and by calculating a range of reliability statistics. Strategies are suggested to increase reliability in the use of actuarial tools in routine practice.