Application of the Iscan method to two- and three-dimensional imaging of the sternal end of the right fourth rib

Age determination is a major field of interest in physical and forensic anthropology. Among the different methods based on macroscopic skeletal study, the Iscan method, which analyzes the sternal end of the right fourth rib, is one of the most reliable. We applied the Iscan method to two- and three-dimensional multislice computed tomography (MSCT) reconstructions of the sternal end of the right fourth rib on 39 ribs. The intra-observer variability on MSCT reconstructions was good (gamma coefficient equal to 0.86; value of the Krippendorff's alpha reliability equal to 0.79); inter-observer variability on MSCT reconstructions was also good (gamma coefficient ranging from 0.82 to 0.88; value of the Krippendorff's alpha reliability ranging from 0.78 to 0.86). We demonstrated excellent agreement between the results of analysis of bone samples and those of the two- and three-dimensional images, in particular regarding bone projections, morphology of the pit and of its rim. The accuracy of age estimation did not significantly differ between the Iscan method applied to dry bones and the same method applied to MSCT images. Determination of the Krippendorff's alpha reliability coefficient for the inter-error method confirmed the agreement between phase estimations obtained with the two methods (ranging from 0.55 to 0.71). The real civil age was comprised in 21 cases out of 36 for assessment performed on dry bones and in 23 cases out of 36 on MSCT reconstructions, which represented 58.3% and 63.9%, respectively. Use of MSCT reconstructions in forensic anthropology offers many advantages: no bone preparation, no damage to bone material, and the possibility of application to living individuals.     

Do drug users use less alcohol than non-drug users? A comparison of ethyl glucuronide concentrations in hair between the two groups in medico-legal cases

Two groups were selected from the remainder of hair samples that had been tested for drugs at TrichoTech for medico-legal cases: samples that tested negative (drug-negative group; N=42, age 33.4+/-7.2 years) and samples that tested positive for drugs (drug-positive group; N=57, age 32.5+/-8.8 years). A rapid, simple method to detect the ethanol metabolite, ethyl glucuronide (EtG) in hair has been developed. The hair samples were sectioned, and then submitted to overnight sonication in water. Samples then underwent SPE using anion exchange cartridges, followed by derivatisation with N,O-bis[trimethylsilyl]trifluoroacetamide (BSTFA), before confirmation by GC-MS/MS. The assay produced excellent linearity and sensitivity over the calibration range 0.02-1.0 ng/mg, assuming a 10 mg hair sample. The mean age of the two groups was not statistically different (p=0.575, Student t-test), indicating a homogeneous group. Twelve of the 57 (21.0%) hair samples of the drug-positive group tested positive for EtG, and 17 of the 42 (40.5%) hair samples of the drug-negative group tested positive for EtG. The mean concentration of EtG in the drug-positive group was 0.011 ng/mg compared to 0.107 ng/mg in the drug-negative group. When the full results of this study were subjected to statistical analysis it was shown that EtG levels in the drug-negative group were statistically higher than those found in the drug-positive group (p<0.05). This preliminary finding may be of use in the study of addiction and adds valuable data to previous studies regarding the use of EtG as a valuable marker for alcohol levels in hair.     

‘Reasonable Offers’ As a Defence to Unfair Prejudice Petitions: Prescott v Potamianos

It is long established that a ‘reasonable offer’ for a petitioner's shares can defeat an unfair-prejudice petition. Lord Hoffmann gave guidance about such offers in O'Neill v Phillips. Now, in Prescott v Potamianos, the Court of Appeal has set out three factors that help to determine in general whether an offer is ‘reasonable’. Those factors are: the value offered; the likelihood of implementation; and the proximity to the unfairly prejudicial conduct. The Court's guidance is useful for lawyers and their clients, as well as being broadly favourable for petitioners. But the Court emphasised that the unfair-prejudice jurisdiction is based on fairness and so requires a considerable degree of flexibility. Such flexibility impairs the certainty that Lord Hoffmann was seeking to promote, and may create difficulties for parties making or receiving offers.     

Criminal personality profiling

In this work we examine outcome and process differences in criminal personality profiling among groups of profilers, detectives, psychologists, and students, using closed police cases—one sex offense and one homicide. Two major questions guide this research: (1) Are professional profilers more accurate than nonprofilers in generating personality profiles and correctly identifying offender features from crime scene details? and (2) Is the process that the profilers use qualitatively different from that of the nonprofilers? In the written profile task, the task that is most representative of what profilers actually do, profilers write richer, more detailed, and more valid profiles than the nonprofilers for both the sex offense case and homicide case. An analysis of correct responses concerning the known offender for the sex offense case revealed that the profilers scored significantly better than the other three groups in a variety of measures; similar results were not revealed for the homicide case. Profilers, however, do not appear to process this material in a way qualitatively different from any other group.