Combined Statistical Analyses of Forensic Evidence in Sexual Assault: A Case Report and Brief Review of the Literature

DNA analysis has been widely used in the forensic field in order to contribute to identifying the perpetrator of a crime. Forensic investigation in sexual assaults usually focuses on locating and identifying biological fluids, followed by DNA analysis. The identification of certain compounds present in condoms can be useful to reconstruct the occurred event, especially in cases of sexual assaults where the DNA analysis did not show the presence of a male profile and where RNA analysis did not show the presence of sperm markers. Herein we describe the case of a woman reporting to be victim of sexual assault, who was not able to provide accurate information concerning the dynamics of the event; she remembered only forced penile–vaginal penetration by a single perpetrator. We performed short tandem repeat (STR) analyses and mRNA typing for forensic genetics testing on vaginal and rectal swabs collected on the victim, and Fourier-transform infrared spectroscopy (FTIR) followed by chromatographic analyses for the detection of condom compounds on the same swabs. The STR analysis showed only the victim’s genetic profile, and RNA analysis showed only the presence of vaginal and skin markers. In this situation, the identification of condom compounds residues on vaginal swabs became important as it complemented other collected evidences allowing the Court to reconstruct the events. A proposal of likelihood ratio (LR) calculation for the assessment of the weight of evidence in this case is described.     

Trans Subjectivity and the Spatial Monolingualism of Public Toilets

The built environment and the organisation of public spaces reflect the normative notions of male and female. Public toilets, amongst other widely common public spaces, underline these two opposing concepts and challenge the presence of transgender. Within the boundaries of public toilets, transgender and gender non-conforming individuals become a crucial point of debate, scrutiny and controversy. Analysing the politics of such gender-segregated space, this article explores the notion of uniformity and challenges the idea of single-ness as the absolute expression of the self.     

Quasi-experimental designs for community-level public health violence reduction interventions: a case study in the challenges of selecting the counterfactual

Objectives

We highlight the importance of documenting the step-by-step processes used for the selection of comparison areas when evaluating a community-level intervention that targets a large-scale community.

Methods

We demonstrate the proposed method using a propensity score matching framework for an impact analysis of the Cure Violence Public Health Model in Philadelphia. To select comparison communities, propensity score models are run using different levels of aggregation to define the intervention site. We discuss the trade-offs made.

Results

We find wide variation in documentation and explanation in the extant literature of the methods used to select comparison communities. The size of the unit of analysis at which a community is measured complicates the decision processes, and in turn, can affect the validity of the counterfactual.

Conclusions

It is important to carefully consider the unit of analysis for measurement of comparison communities. Assessing the geographic clustering of matched communities to mirror that of the treated community holds conceptual appeal and represents a strategy to consider when evaluating community-level interventions taking place at a large scale. Regardless of the final decisions made in the selection of the counterfactual, the field could benefit from more systematic diagnostic tools that document and guide the steps and decisions along the way, and ask: “could there have been another way of doing each step, and what difference would this have made?” Overall, across community-level evaluations that utilize quasi-experimental designs, documentation of the counterfactual selection process will provide a more fine-grained understanding of causal inference.

     

Demonstrating Access to Public Services Diagrammatically

The Nomogramma di Gandy is a practical analytical tool and presentational method that can be applied to the subject of access to public services, such as universities, prisons, and hospitals. Illustrative examples are provided. It is flexible, requires minimal data, and can compare access across many geographical areas in one presentation. It addresses the need to appreciate the dynamics that can exist behind summary statistical analyses that focus on net changes, and can show trends over time. Such visual scanning of multiple data points and their relative juxtapositions, enables many common thinking errors to be minimized, if not completely avoided.