Stranger sexual homicide: an exploratory behavioural analysis of offender crime scene actions

ABSTRACT

This study explores the role and function of homicidal and sexual violence in cases of stranger sexual homicide. The aim was to determine whether the instrumental/expressive hypothesis of physical violence and the overt/covert hypothesis of sexual violence applies to this crime. The method involved an analysis of the crime scene actions of 81 British stranger sexual killers using multidimensional scaling. Results suggest the instrumental/expressive hypothesis of physical violence and the overt/covert hypothesis of sexual violence does apply to stranger sexual homicide but they manifest as instrumental/overt and expressive/covert superordinate themes comprising four sub-themes reflecting rape, impersonal sexual assault, overkill and control. Although these superordinate themes can explain some stranger sexual homicides, a key hypothesis of this study is that the four sub-themes can also combine into different superordinate themes, knowledge of which can aid our understanding of this serious and deviant form of interpersonal violence.     

Variation in decomposition stages and carrion insect succession in a dry tropical climate and its effect on estimating postmortem interval

Insects have an important role in minimum postmortem interval (PMI_min) estimation. An accurate PMI_min estimation relies on a comprehensive study of the development and succession of local carrion insects. No published research on carrion insect succession exists for tropical north Queensland. To address this, we aimed to obtain preliminary observational data concerning the rate of decomposition and insect succession on pig carcasses in Townsville and compare these with other regions of Australia and overseas. Adult insects were collected daily from three pig carcasses for 30 d during summer and identified to family level. Observations of decomposition rate were made each day and progression through the stages of decomposition were recorded. Adult insects were identified to family and their presence/absence used as a proxy for arrival at/departure from the remains, respectively. These preliminary data highlight several interesting trends that may be informative for forensic PMI_min estimation. Decomposition was rapid: all carcasses were at the dry/remains stage by Day 5, which was substantially quicker than all other regions in the comparison. Differences were also observed in the presence/absence of insect families and their arrival and departure times. Given the rapid progression through early decomposition, we argue that later-arriving coleopteran taxa may be more forensically informative in tropical Australia, in contrast with temperate regions where Diptera appear most useful. This research contributes preliminary observational data to understanding insect succession patterns in tropical Australia and demonstrates the critical need for comprehensive local succession data for each climatic region of Australia to enable accurate PMI_min estimation. These data will inform future research targeted at gaining a more comprehensive understanding of insect succession in the Australian tropics.

Key points:

• We obtained preliminary observational data concerning the rate of decomposition and insect succession on pig carcasses in tropical Australia.
• Decomposition was rapid: all carcasses were at the dry/remains stage by Day 5.
• Coleopteran taxa may be more forensically informative in tropical Australia than dipterans.

     

Analysis and discrimination of electrical tapes: part II. Backings

The backings of 90 black electrical tapes were analyzed to evaluate the chemical components of these films, the ability of individual techniques to discriminate samples, and the ability of the techniques combined to distinguish samples. The techniques utilized and their respective discrimination results were stereomicroscopy and physical measurements, to include observation of surface features of the backing, width, and thickness measurements (c. 64%); Fourier transform infrared spectroscopy (FTIR) using a microscope accessory (c. 83%); pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS; c. 81%); and scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS; c. 87%). Ninety-four percent of the backings were discriminated through this combination of analytical methods. Finally, evaluating these results in conjunction with previously published data on the analysis of the adhesives from the same set of electrical tapes provided an overall discrimination of nearly 96%.     

Regulating tissue research: do we need additional rules to protect research participants?

This article explores whether additional rules are needed for the regulation of tissue research in Europe. A human rights-based approach (referring to international documents and illustrative examples from national legislation) is taken to address the question: what is so special about tissue, in particular when compared to personal data? The existing regimes in Europe on data protection and clinical trials are presented and examined for their suitability to govern tissue research, taking into account the differences between data and tissue. Six recommendations are outlined, highlighting important points future legislation on tissue research must take into account.     

The economic analysis of antitrust consents

Henry G. Manne, our friend, Mentor, and colleague, was a pioneer in the economic analysis of law. By consistently challenging the notion that existing institutions were well understood, he expanded the domain of economics to new and fertile ground. In that spirit, our goal in this article is to bring out of the shadows an institution that has thus far evaded the light of economic analysis: antitrust consents. In our view, competition authorities around the world should be asking themselves what ratio of litigation to settlement is optimal for their agency. Over the last 35 years, the United States Federal Trade Commission and the Antitrust Division of the Department of Justice have shifted dramatically toward greater reliance upon consent decrees than upon litigation to resolve antitrust disputes. As an aid to national competition agencies considering the desirability of adopting a similar approach, we focus upon the importance of economic analysis in evaluating movement along the continuum from a law enforcement model to a regulatory model of agency behavior. We draw upon the U.S. experience to substantiate our claim that the costs associated with a shift toward the regulatory model, including the potential distortion in the development of substantive antitrust doctrine, may be under-appreciated and discernable only in the long run. We acknowledge that consent decrees can and should be an important tool in an antitrust agency’s toolkit for resolving antitrust disputes. We contend, however, that a full economic analysis of reliance primarily upon consent decrees is necessary to inform each competition agency’s strategic decision about the optimal mix of law enforcement and regulatory techniques.     

Understanding the Authoritative Parenting–Early Adolescent Tobacco Use Link: The Mediating Role of Peer Tobacco Use

Eighth-grade students (N = 156) completed questionnaires in which they reported on their perceptions of parents' warmth, structure, and psychological autonomy granting (used to create an index of authoritative parenting) and their own levels of tobacco use. Adolescents were also asked to list the names of other students at their school with whom they spent time (friends). Independent reports obtained from these friends were used to form an index of the mean level of tobacco use among each adolescent's friends. Higher levels of authoritative parenting were associated with lower levels of tobacco use among target adolescents. The association between parental authoritativeness and adolescent tobacco use was mediated by levels of tobacco use among peers. An amplification effect was observed in which adolescents were particularly unlikely to use tobacco products when they both received authoritative parenting at home and were members of non-tobacco-using peer groups.     

The use of quantitative light-induced fluorescence (QLF) to identify composite restorations in forensic examinations

There has been a large increase in the number of tooth colored restorations "white fillings" placed in recent years. An increased demand from the public for more aesthetic dental restorations causes a potential problem for forensic dentists who may find the fillings difficult to identify and hence include in postmortem odontograms. This has implications for the accuracy of dental identifications, particularly in situations where limited time is available for postmortem identification, e.g., mass casualty incidents. A new method for the detection of composite restorations is presented. Quantitative Light-induced Fluorescence (QLF) is a technique currently employed to detect small changes in enamel mineral content. An experiment was conducted to determine if the technique would afford a greater degree of contrast between composite and enamel and thus enable the accuracy of composite identification in enamel. Twenty-four previously extracted human premolars were gently cleaned with pumice and wet-and-dry paper. Twelve were subsequently randomly selected and restored on their buccal surfaces with Spectrum (a composite) following manufacturer's instructions. No attempt was made to color match the teeth and all were filled with shade B3. Twelve teeth were left unrestored. QLF and normal white light images were taken of both restored and non-restored surfaces with teeth wet and then dried. Ten forensic dentists were asked on two separate occasions (one month between each attempt) to indicate whether or not they thought the surface was: a) restored or b) unrestored. Results indicate that forensic dentists detected a significantly higher proportion (p<0.005) of filled surfaces with QLF.