Handwriting evidence evaluation based on the shape of characters: application of multivariate likelihood ratios

A novel Bayesian methodology has been developed to quantitatively assess handwriting evidence by means of a likelihood ratio (LR) designed for multivariate data. This methodology is presented and its applicability is shown through a simulated case of a threatening anonymous text where a suspect is apprehended. The shape of handwritten characters a, d, o, and q of the threatening text was compared with characters of the true writer, and then with two other writers, one with similar and one with dissimilar characters shape compared to the true writer. In each of these three situations, 100 draws of characters were made and the resulting distributions of LR were established to consider the natural handwriting variation. LR values supported the correct hypothesis in every case. This original Bayesian methodology provides a coherent and rigorous tool for the assessment of handwriting evidence, contributing undoubtedly to integrate the field of handwriting examination into science.     

Nanotechnology for forensic sciences: Analysis of PDMS replica of the case head of spent cartridges by optical microscopy, SEM and AFM for the ballistic identification of individual characteristic features of firearms

A novel application of replica molding to a forensic problem, viz. the accurate reproduction of the case head of gun and rifle cartridges, prior and after been shot, is presented. The fabrication of an arbitrary number of identical copies of the region hit by the firing pin and by the breech face is described. The replicas can be (i) handled without damaging the original evidence, (ii) distributed to different law enforcement agencies for comparison against other evidences found on crime scenes or ballistic tests of seized firearms, (iii) maintained on a file by the laboratories. A detailed analysis of the morphological features of the replicas has been carried out by standard microscopy techniques as well as by advanced microscopy such as scanning probe and scanning electron leading to a quantitative morphological characterization of the case heads down to the nanometer scale. The assignment of the cartridge replicas to the shooting weapon is demonstrated to hold below the micron scale, while it is hindered at the nanometer level both by the manufacturing differences and by eventual modifications occurring on the firing pin.     

Uncertainty about the true source. A note on the likelihood ratio at the activity level

This paper focuses on likelihood ratio based evaluations of fibre evidence in cases in which there is uncertainty about whether or not the reference item available for analysis - that is, an item typically taken from the suspect or seized at his home - is the item actually worn at the time of the offence. A likelihood ratio approach is proposed that, for situations in which certain categorical assumptions can be made about additionally introduced parameters, converges to formula described in existing literature. The properties of the proposed likelihood ratio approach are analysed through sensitivity analyses and discussed with respect to possible argumentative implications that arise in practice.     

Bayesian networks and the value of the evidence for the forensic two-trace transfer problem*

Forensic scientists face increasingly complex inference problems for evaluating likelihood ratios (LRs) for an appropriate pair of propositions. Up to now, scientists and statisticians have derived LR formulae using an algebraic approach. However, this approach reaches its limits when addressing cases with an increasing number of variables and dependence relationships between these variables. In this study, we suggest using a graphical approach, based on the construction of Bayesian networks (BNs). We first construct a BN that captures the problem, and then deduce the expression for calculating the LR from this model to compare it with existing LR formulae. We illustrate this idea by applying it to the evaluation of an activity level LR in the context of the two-trace transfer problem. Our approach allows us to relax assumptions made in previous LR developments, produce a new LR formula for the two-trace transfer problem and generalize this scenario to n traces.     

From unknown to known: Identification of the remains at the mausoleum of fosse Ardeatine

During the Second World War, on 24th March 1944, 335 Italians were massacred near Rome by the occupying forces of Nazi Germany. Four months later forensic examination led to the identification of 323 out of 335 victims. After approximately 60?years, the identification of the remaining unidentified twelve victims began with anthropological and genetic analysis carried out by a team of Italian forensic experts. Anthropological analysis was performed in field in order to confirm the sex of each victim and verify the presence of only one individual in each grave for a correct sampling. Selected bone fragments for each individual were then collected and transferred to the laboratory for genetic analysis. Although the anthropological ante mortem information was limited, morphological and metrical data was collected for a possible future identification of the victims. Subsequently, the typing of autosomal loci, Y-STR and mtDNA D-loop region of all bone and available reference samples was conducted. LR and cumulative LRs obtained from autosomal STR and Y-STR results confirmed the alleged relationship between three victims and their relatives with values over 10⁴ (one sample) and 10⁶ (two samples). Therefore, the genetic analysis offered the families the possibility of replacing the number of the grave with the name of the victim.     

Allele frequencies and statistical parameters for Penta E and Penta D STR loci in Córdoba (Argentina) population

POPULATION: Urban and countryside population of Córdoba (Argentina).     

Cross Border Health Care: An Analysis of Recent ECJ Rulings

Recent rulings of the European Court of Justice show a trend towards a virtual European health-care basket. Four developments underlie this trend. First, the competence of the European Union seems to mature in the field of health care. Secondly, through a variety of authorisation procedures, individual Member States can to a large extent determine the conditions for cross border care. Thirdly, recent court cases indicate that the co-ordination of cross border care increasingly becomes a EU matter. Finally, in particular border regions, more flexible procedures for cross border care are being developed. An analysis of these developments from an (economic) institutional/constitutional point of view shows that potential Pareto-improvements can be expected from recent changes. These improvements depend on the institutional/constitutional framework into which these rules and engagements are embedded. Our analysis suggests that, although the current (increasing) role for the EU seems desirable, diminishing the role that individual Member States can play is not. National authorisation procedures, local/regional arrangements and flexible rulings are mechanisms that can secure an efficient level of output and an optimal size of the jurisdiction responsible for cross border care. This leads to the following recommendations: Current authorisation procedures (which differ per Member State) have to be maintained in order to secure an optimal community size for cross border services and goods; Bilateral agreements and flexible procedures in cross border regions should be stimulated in order to adapt institutional arrangements to the demand for cross border care by (a group of) individuals. The increased competency of the EU in the field of health care can best be used to make authorisation procedures more consistent and stimulate regional cross border care arrangements.     

Conveners as champions of collaboration in the public sector: a case from South Africa

This article analyses the role of conveners in facilitating interorganisational collaboration. Consistent with previous research, the article shows that conveners help overcome the obstacles frequent in interorganisational collaboration processes. It also illustrates further how their effectiveness depends on their credibility among the partners, their familiarity with the collaborative project and their being perceived as unbiased intermediaries. Most interestingly, the article advances our knowledge on conveners by suggesting that their behaviour is consistent with that common among ‘champions’ of innovation. They are likely to assume a leadership role and use influence politics, such as salesmanship, personal appeal and persuasion. These findings build on a case study of successful collaboration between two government agencies in South Africa. We believe, however, that the findings are likely to apply to other types of organisation, private and voluntary, and to other country contexts. Copyright © 2003 John Wiley & Sons, Ltd.