Interdisciplinary cooperation of forensic sciences--results of a simulation exercise

In a workshop held on the occasion of the foundation of the INFW, the Interdisciplinary Network of Forensic Sciences (www.infw.org), 14 scientists from 10 fields of expertise were allotted to 3 teams. Each team had to independently solve the same fictitious forensic case. In this, several corpses or skeletons in varying degrees of decomposition were found in the remains of an old bunker during a large building project. After a set time limit of 45 minutes, the approaches to the task were noted on individual flipcharts by each team. A comparison of the solutions suggested by the three very heterogeneously composed teams revealed a high degree of similarity. However, particularly the "exotic" disciplines developed surprising approaches. The experiment was an interesting and instructive experience for all participants and underscores the necessity of interdisciplinary cooperation in solving complex forensic questions.     

The RECON typology of stalking: reliability and validity based upon a large sample of North American stalkers

A new typology of stalking, RECON (relationship and context-based), is proposed, based upon the prior relationship between the pursuer and the victim, and the context in which the stalking occurs. The static typology yields four groups: Intimate, Acquaintance, Public Figure, and Private Stranger. The typology was tested on a large (N = 1005) nonrandom sample of North American stalkers gathered from prosecutorial agencies, a large police department, an entertainment corporation security department, and the authors' files. Interrater reliability for group assignment was 0.95 (ICC). Discriminant validity (p < 0.01) was demonstrated on a variety of demographic, clinical, pursuit, threat, and violence characteristics among and between groups. Findings confirm and extend the work of other researchers, most notably the very high risk of threats and violence among prior sexually intimate stalkers, the very low risk of threats and violence among public figure (celebrity) stalkers, and the negative relationship between stalking violence and psychosis.     

Forensic analysis of bicomponent fibers using infrared chemical imaging

The application of infrared chemical imaging to the analysis of bicomponent fibers was evaluated. Eleven nominally bicomponent fibers were examined either side-on or in cross-section. In six of the 11 samples, infrared chemical imaging was able to spatially resolve two spectroscopically distinct regions when the fibers were examined side-on. As well as yielding characteristic infrared spectra of each component, the technique also provided images that clearly illustrated the side-by-side configuration of these components in the fiber. In one case it was possible to prepare and image a cross-section of the fiber, but in general the preparation of fiber cross-sections proved very difficult. In five of the 11 samples, the infrared spectra could be used to identify the overall chemical composition of the fibers, according to a published classification scheme, but the fiber components could not be spatially resolved. Difficulties that are inherent to conventional "single-point" infrared spectroscopy, such as interference fringing and sloping baselines, particularly when analyzing acrylic type fibers, were also encountered in the infrared chemical image analysis of bicomponent fibers. A number of infrared sampling techniques were investigated to overcome these problems, and recommendations for the best sampling technique are given. Chemical imaging results were compared with those obtained using conventional fiber microscopy techniques.     

A simple and inexpensive molecular method for sexing and identification of the forensic samples of elephant origin

The population of the Asian elephant is being dramatically reduced due to poaching of the ivory from the male. As poaching occurs in remote forests, it often takes weeks or longer for it to be discovered and it is therefore often very difficult to determine the sex of the decomposed body. Data suggest that in the recent past, over 2000 male elephants have been poached in South India. We have developed a technique based on molecular markers to determine that the carcass is an elephant and that it is a male. Using DNA sequence information from Genbank, we have developed two primer pairs: one for the mitochondrial DNA (mtDNA) and the other for the sex-determining region of Y chromosome (SRY) gene of the Indian elephant. After PCR amplification of known elephant DNA, we found that the mtDNA was common in both males and females, whereas the SRY-specific amplicon was observed only in the male.     

Blunt force cranial trauma in the Cambodian killing fields

In this paper we present a unique pattern of blunt force cranial trauma that was observed in 10 of a sample of 85 crania from a Cambodian skeletal collection comprised of Khmer Rouge victims. Initial examination of the trauma, which presents as substantial damage to the occipital with fractures extending to the cranial base, suggested the pattern was classifiable as a basilar or ring fracture. However, further investigation, including trauma analysis and historical research, revealed that this fracture type is distinctive from basilar and ring fractures. Historical data indicate that a particular execution method was the likely source of the trauma. Recognition of this trauma pattern is significant because it exemplifies the distinct fracture configuration resulting from an apparently categorical and methodical execution technique. Identification of this fracture type could potentially assist forensic investigators in the recognition of specific methods of murder or execution.     

Microbial metagenome profiling using amplicon length heterogeneity-polymerase chain reaction proves more effective than elemental analysis in discriminating soil specimens

The combination of soil's ubiquity and its intrinsic abiotic and biotic information can contribute greatly to the forensic field. Although there are physical and chemical characterization methods of soil comparison for forensic purposes, these require a level of expertise not always encountered in crime laboratories. We hypothesized that soil microbial community profiling could be used to discriminate between soil types by providing biological fingerprints that confer uniqueness. Three of the six Miami-Dade soil types were randomly selected and sampled. We compared the microbial metagenome profiles generated using amplicon length heterogeneity-polymerase chain reaction analysis of the 16S rRNA genes with inductively coupled plasma optical emission spectroscopy analysis of 13 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Si, and Zn) that are commonly encountered in soils. Bray-Curtis similarity index and analysis of similarity were performed on all data to establish differences within sites, among sites, and across two seasons. These data matrices were used to group samples that shared similar community patterns using nonmetric multidimensional scaling analysis. We concluded that while chemical characterization could provide some differentiation between soils, microbial metagenome profiling was better able to discriminate between the soil types and had a high degree of reproducibility, therefore proving to be a potential tool for forensic soil comparisons.     

Prevalence of mental disorders and deliberate self-harm in Greek male prisoners

The aim of this survey was to determine the prevalence of current and lifetime mental disorder and deliberate self-harm among male prisoners in Greece. The subjects were 80 randomly selected remanded and sentenced prisoners in a Greek prison. They were assessed for mental disorder including suicidality and substance misuse using the Mini International Neuropsychiatric Interview (MINI). We also collected information regarding contact with psychiatric services, previous deliberate self-harm as well as physical health and conducted a brief assessment of their intellectual functioning. Mental disorder was diagnosed in 63 (78.7%) prisoners. The main diagnoses were: anxiety disorder, 30 (37.5%); major depression, 22 (27.5%); antisocial personality disorder, 30 (37.5%); alcohol dependence, 21 (26.3%) and opiate dependence 22 (27.5%) and schizophrenic or bipolar disorder 9 (11.2%). Deliberate self-harm prior to and during imprisonment was reported by 15% and 2.5% of prisoners, respectively, and 12 prisoners (15%) had IQ below 75. This survey identified a significant level of need for specialist mental health services in prison. Further studies are required to assess the specific needs of those patients who are too unwell to remain in prison, the need for specific treatments for substance misuse and improved assessment/treatment of common psychiatric disorders.     

Adults’ Judgments of Children's Coached Reports

This study investigated adults’ judgments of the honesty of children's coached true and fabricated mock testimony. Adults saw video clips of children testifying in a mock court about a true or fabricated event in their lives. They were asked to make an assessment of the truthfulness of the testimony, and respond to questions about their perception of children's credibility. Half of the adults saw children testifying after a competence examination, and the other half saw children testifying without a competence examination. Overall, girls were rated as more competent than boys, and their testimony was more likely to be believed. Younger children were more likely to be rated as incompetent than older children. A factor analysis of adults’ responses revealed six factors which significantly predicted adults’ overall assessment of children's credibility, and their evaluations of children's competence to testify. Adults’ detection accuracy was at chance, with the majority of children rated as truthful. Viewing the competency examination and cross-examination did not improve the adults’ detection accuracy. However, seeing the cross-examination made adults’ less likely to believe children's testimony. The implications of these results for the judicial system are discussed.