Calculating likelihood ratios for a mixed DNA profile when a contribution from a genetic relative of a suspect is proposed

This technical note describes a practical method for evaluating evidence in the case of a two person conditioned DNA mixture where the defence proposition is that the unknown contributor is genetically related to the suspect. A conditioned mixture is one where the presence of DNA from one of two individuals is accepted by both prosecution and defence. A typical example would be a vaginal swab in an alleged rape case, where the presence of the complainant's DNA would be expected and samples have been taken from the complainant and a suspect. Much has been written about the interpretation of such mixtures and the calculation of the conditional genotype probabilities that must be carried out. In general, such treatments assume that the unknown contributor, under the defence proposition, is unrelated to the known individuals. In this paper, we consider the case where the defence proposition is that the unknown contributor is genetically related to the suspect. We describe a method, incorporating a flow chart and reference tables that facilitate manual calculations of the likelihood ratio for several postulated genetic relationships.     

Trichophyton Mentagrophytes Perforates Hair of Adult Corpses in the Gaseous Period*

Abstract: Despite the substantial literature on mycology, there are still limited reports of the interaction between fungi and human hosts in the postmortem period. Thus, the main goal of this study was to investigate the in vitro perforation test using Trichophyton mentagrophytes on hair from adult corpses in the postmortem period (gaseous period). The protocol was carried out with positive (prepubescent children’s hair) and negative controls (healthy adult hair) as well. One strain of Trichophyton rubrum was also used as a negative perforation control. Perforations were found in all the hair samples from corpses and prepubescent children after 12–14 days exposure to T. mentagrophytes and were absent in the hair samples of healthy adults. Furthermore, hair perforation was not observed with T. rubrum. Our preliminary findings suggest the use of T. mentagrophytes as a potential marker of the death interval in forensic science.     

Computational Approach to Identify Different Injuries by Firearms

Complications arise in the analysis of gunshot wounds to the maxillofacial region, when neither the projectile nor the gun is found at the crime scene. We simulated 5‐ and 15‐cm firing distances at a human mandible to investigate the external morphology of entrance wounds based on fire range. The ammunition models, .40‐caliber S&W, .380‐caliber, and 9 × 19‐mm Luger, were constructed with free‐form NURBS surfaces. In a dynamic simulation, projectiles were fired against mandibular body 3D model at 5 and 15 cm. All entrance wounds presented oval aspect. Maximum diameter and von Mises stress values were 16.5 mm and 50.8 MPa, both for .40‐caliber S&W fired at 5 cm. The maximum energy loss was 138.4 J for .40 S&W fired at 15 cm. In conclusion, the mandible was most affected by .40‐caliber S&W and morphological differences were observable in holes caused by different incoming projectile calibers fired at different distances.     

Toward Normalization of Defamation Law: The U.K. Defamation Act of 2013 and the U.S. SPEECH Act of 2010 as Responses to the Issue of Libel Tourism

In the wake of several high-profile libel actions brought by U.S. celebrities and foreign businessmen in London because of more favorable defamation laws there, London was dubbed the “libel tourism capital of the world.” The U.S. response in 2010 was the passage of the SPEECH Act, preventing courts from enforcing libel judgments from foreign jurisdictions not providing the same level of protection as the United States. Similarly, in 2013 the United Kingdom responded to international and national criticism by passing the Defamation Act to address the loophole in its system that caused the abuse. Both acts have been criticized, the first for its aggressiveness, and the second for its conservative nature. This article examines the development of the law of defamation in the two jurisdictions and analyzes the content of both statutes, along with their criticisms, proposing international cooperation to address the issue of libel tourism.     

Human Trafficking for Criminal Exploitation: The Failure to Identify Victims

Human trafficking for criminal exploitation is one of the lesser-known forms of human trafficking. The failure of the criminal justice system to identify the victims of this type of trafficking can lead to a failure to take the victim-centred approach to trafficking espoused in the international legal instruments that regulate the matter, an approach that emphasises the protection of victims and respect for their rights. In light of earlier findings of the existence of unidentified victims of human trafficking for criminal exploitation in several European countries — the UK, Ireland, Spain, the Czech Republic and the Netherlands — a qualitative study was conducted, consisting of 37 in-depth interviews with practising criminal justice professionals and victim service providers in Spain. Because undetected victims of human trafficking for criminal exploitation are usually treated as offenders, the main aim of this research with professionals was to determine the causes of the criminal justice system’s failure to identify the victims of this specific form of trafficking in order to prevent them from remaining hidden victims.     

Diel Activity and Effect of Carcass Decomposition on the Attractiveness to the Forensically Important Species Oxelytrum Discicolle (Coleoptera: Silphidae)†

Oxelytrum discicolle is a carrion beetle commonly found in the Neotropical region, mainly associated with cadavers and carcasses. Information on behavior related to the likelihood of cadaver colonization is scarce. We performed two field experiments in peri‐urban forest in Brazil in order to strengthen our knowledge on O. discicolle behavior. In the first experiment, we assessed the preference for piglet carcasses at different stages of decomposition offered simultaneously in two seasons, dry and rainy, while in the second experiment we investigated the diel activity of adults. A total of 493 adults were collected in the experiments. A significantly higher abundance was detected in the rainy season. There was a marked preference for carcasses at advanced stages. Adults exhibited a typical nocturnal behavior, the number trapped at night was 17 times greater than those collected during the day. Oxelytrum discicolle is nocturnal species that prefers carcasses in advanced stage of decomposition.     

Enucleation in psychosis associated with aqueductal stenosis

Reports of self-enucleation are frequent in medical literature, but cases of enucleation towards another are rare. We report the case of a man, 20 years of age, who suffered from psychosis with hydrocephalus and aqueductal stenosis that required a forensic psychiatric investigation to ascertain whether he was of unsound mind when he assaulted and enucleated the right eye of an officer and led to the surgical enucleation of the victim's left eye. Based on his clinical interviews and hospitalization record, we conclude that at the time of the assault, he was suffering from a delusional disorder with religious and demonic content, visual and auditory hallucinations, illusion phenomena, delusional interpretations, imaginative elements, a feeling of terror, and command hallucinations that compelled him to perform the act of aggression.     

Results of the GEP-ISFG collaborative study on the Y chromosome STRs GATA A10, GATA C4, GATA H4, DYS437, DYS438, DYS439, DYS460 and DYS461: population data

The Spanish and Portuguese ISFG Working Group (GEP-ISFG) carried out a collaborative exercise in order to asses the performance of two Y chromosome STR tetraplexes, which include the loci DYS461, GATA C4, DYS437 and DYS438 (GEPY I), and DYS460, GATA A10, GATA H4 and DYS439 (GEPY II). The groups that reported correct results in all the systems were also asked to analyse a population sample in order to evaluate the informative content of these STRs in different populations. A total of 1020 males out of 13 population samples from Argentina, Brazil, Costa Rica, Macao, Mozambique, Portugal and Spain were analysed for all the loci included in the present study. Haplotype and allele frequencies of these eight Y-STRs were estimated in all samples. The lowest haplotype diversity was found in the Lara (Argentina) population (95.44%) and the highest (99.90%) in Macao (China). Pairwise haplotype analysis showed the relative homogeneity of the Iberian origin samples, in accordance with what was previously found in the European populations for other Y-STR haplotypes (http://www.ystr.org). As expected, the four non-Caucasian samples, Macao (Chinese), Mozambique (Africans), Costa Rica (Africans) and Argentina (Lara, Amerindians), show highly significant Phist values in the pairwise comparisons with all the Caucasian samples.