Cocaine profiling for strategic intelligence purposes, a cross-border project between France and Switzerland. Part I. Optimisation and harmonisation of the profiling method

Optimisation and harmonisation of analytical and statistical methodology have been carried out between two forensic laboratories (Lausanne, CH and Lyon, F) in order to provide drug intelligence for cross-border cocaine seizures. The aim was to improve the gas chromatographic analysis of cocaine samples for profiling. Some important validation parameters were tested to verify the developed method and demonstrate its profiling capacity: the selectivity of the method with retention time reproducibility, the choice of a derivatisation agent improving the chromatography (MSTFA, BSA, TMSI and BSTFA+TMCS 1%), the cutting agents influence (matrix effect), the influence of the sample storage conditions and the sample quantity to weigh for analyses. Eight main alkaloids, which represent the sample signature, have been selected: ecgonine methyl ester, ecgonine, tropacocaine, benzoylecgonine, norcocaine, cis- and trans-cinnamoylcocaine and 3,4,5-trimethoxycocaine. Their stability in the solvent used (CHCl(3)/pyridine) was demonstrated. In order to reach the final objective, which is the comparison of samples seized and analyzed in two different laboratories, the harmonisation of the profiling method between the two laboratories had to be ensured and is the subject of ongoing research.     

Different assays for hingamine in the study of biological fluids

The authors present a method of hingamine identification in non-biological substances (tablets, powder, syringes) and biological fluids (blood, urine). Isolation was made with chloroform in pH 10. Identification was conducted with thin-layer chromatography, gas chromatography/mass-spectrometry, high-performance liquid chromatography, spectrophotometry in UV region. The quantity was estimated with spectrophotometry in UV region, high-performance liquid chromatography and high-performance thin-layer chromatography. The results of the three methods are comparable.     

Public Eyewitness Confidence Can Be Influenced by the Presence of Other Witnesses

Four experiments were conducted to examine whether witnesses' public confidence ratings differ from their private ratings when there are social pressures to use confidence as an impression-management tool. In all four experiments, participants answered questions about a source event (a series of faces in the first three experiments and a simulated crime scene in the fourth). Half of the responses and confidence ratings were given privately and anonymously, and half were given publicly in front of one or more mock jurors. Two central findings emerged from the results. First, public confidence differed from private confidence only when there was more than one witness; when there were no other witnesses, public and private confidence were the same. Second, the direction of the change in public confidence in the multiple-witness settings was influenced by whether or not there was a possibility of being contradicted by the other witnesses. When there was no chance that the participants' responses could be contradicted, they raised their confidence ratings in public; when there was a chance that the other witnesses might contradict them, the participants lowered their public confidence ratings. The results are discussed in terms of self-presentation theory and implications for the legal system.     

Youth Psychopathy and Criminal Recidivism: A Meta-Analysis of the Psychopathy Checklist Measures

Although narrative reviews have suggested that "youth psychopathy" is a strong predictor of future crime and violence, to date no quantitative summaries of this literature have been conducted. We meta-analyzed recidivism data for the Psychopathy Checklist measures across 21 non-overlapping samples of male and female juvenile offenders. After removing outliers, psychopathy was significantly associated with general and violent recidivism (r (w)'s of .24 and .25, respectively), but negligibly related to sexual recidivism in the few studies examining this low base rate outcome. Even after eliminating outliers, however, considerable heterogeneity was noted among the effects, with some of this variability being explained by the gender and ethnic composition of the samples. Effect sizes for the small number of female samples available for analysis were mostly small and nonsignificant, and psychopathy was a weaker predictor of violent recidivism among more ethnically heterogeneous samples. In relation to predicting both general and violent recidivism, psychopathy performed comparably to an instrument designed specifically to assess risk, the Youth Level of Service/Case Management Inventory (Hoge & Andrews, 2002).     

Y-STRs in forensic medicine: DNA analysis in semen samples of azoospermic individuals

ABSTRACT: The incidence of rape has increased, especially in metropolitan areas, such as the city of São Paulo. In Brazil, studies about it have shown that the majority of this type of crime is committed by the relatives and persons close to the victim. This has made the crime more difficult to be denounced, as only 10% of the cases are reported to competent police authorities. Usually, cytological exams are carried out in sex crime investigations. The difficulty in showing the presence of spermatozoa is frequent, but it does not exclude the presence of male DNA. The absence of spermatozoa in material collected from rape victims can be due to several factors, including the fact that the agressor suffers from azoospermia. This condition can be the result of a successful vasectomy. As the majority of DNA in the ejaculation sample is from spermatozoa, there is much less DNA to be analyzed. This study presents the application of Y‐STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) in DNA analysis of sperm samples from 105 vasectomized men. The study demonstrated a great variation in DNA concentration. DNA extraction and amplification was possible in all sperm samples even in the absence of spermatozoa. The same profile was observed, for each individual, from DNA extracted from blood, pre‐ and postvasectomy semen samples. The use of markers specific for Y chromosome in sex crime cases, especially in the absence of spermatozoa, is very important, mainly because in most situations there is a small quantity of the agressor's DNA in the medium and a large quantity of the victim's DNA.     

Measuring the intercondylar shelf angle using radiographs: intra- and inter-observer error tests of reliability

This study presents a test of intra- and inter-observer measurement error rates of the intercondylar shelf angle of the distal femur, as measured on lateral radiographs. This measurement is the central element of a method to determine racial affiliation from the distal femur. Four observers independently radiographed a set of 33 complete and partial femora from collections housed at the Joint POW/MIA Accounting Command, Central Identification Laboratory. Each observer then measured the intercondylar shelf angles in each radiograph, following the original method's guidelines. A supplementary inter-observer error test was conducted by four additional observers on one set of radiographs. Statistically significant differences were found for both intra- and inter-observer error based on the results of Student's t-tests, paired samples t-tests, and ANOVA analyses. The results of this study indicate that further experimentation should be undertaken in order to develop refined measurement techniques that may help improve standardization and reduce the observer error rates.     

Methyl 3-[3',4'-(methylenedioxy)phenyl]-2-methyl glycidate: an ecstasy precursor seized in Sydney, Australia

Five 44 gallon drums labeled as glycidyl methacrylate were seized by the Australian Customs Service and the Australian Federal Police at Port Botany, Sydney, Australia, in December 2004. Each drum contained a white, semisolid substance that was initially suspected to be 3,4-methylenedioxymethylamphetamine (MDMA). Gas chromatography-mass spectroscopy (GC/MS) analysis demonstrated that the material was neither glycidyl methacrylate nor MDMA. Because intelligence sources employed by federal agents indicated that this material was in some way connected to MDMA production, suspicion fell on the various MDMA precursor chemicals. Using a number of techniques including proton nuclear magnetic resonance spectroscopy ((1)H NMR), carbon nuclear magnetic resonance spectroscopy ((13)C NMR), GC/MS, infrared spectroscopy, and total synthesis, the unknown substance was eventually identified as methyl 3-[3',4'(methylenedioxy)phenyl]-2-methyl glycidate. The substance was also subjected to a published hydrolysis and decarboxylation procedure and gave a high yield of the MDMA precursor chemical, 3,4-methylenedioxyphenyl-2-propanone, thereby establishing this material as a "precursor to a precursor."     

Estimation of age-at-death for adult males using the acetabulum, applied to four Western European populations

Methods to estimate adult age from observations of skeletal elements are not very accurate and motivate the development of better methods. In this article, we test recently published method based on the acetabulum and Bayesian inference, developed using Coimbra collection (Portugal). In this study, to evaluate its utility in other populations, this methodology was applied to 394 specimens from four different documented Western European collections. Four strategies of analysis to estimate age were outlined: (a) each series separately; (b) on Lisbon collection, taken as a reference Coimbra collection; (c) on Barcelona collection, taken as a reference both Portuguese collections; and (d) on London collection taken as reference the three Iberian collections combined. Results indicate that estimates are accurate (83-100%). As might be expected, the least accurate estimates were obtained when the most distant collection was used as a reference. Observations of the fused acetabulum can be used to make accurate estimates of age for adults of any age, with less accurate estimates when a more distant reference collection is used.     

Child Abuse-Related Homicides in New Mexico: A 6-year Retrospective Review

Abstract:  We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected.     

Multiple Self‐Inflicted Stab Wounds to Neck,Chest and Abdomen as a Unique Manner of Suicide

Abstract: This is a case report of a 30‐year‐old man found dead in his flat lying on the floor with multiple stab wounds over the body, surrounded by an extensive volume of blood. Examination of the scene of death showed a secure flat, locked from inside. A blood‐stained knife was present close to the body and two unstained notes left on the sofa at the locus. A small plastic bag containing white powder (which following toxicological examinations appeared to be cocaine) and an almost full bottle of beer were present on a table. Autopsy revealed more than 40 stab wounds to neck, chest, and abdomen arranged in isolated groups within which the wounds showed similar directions and had a transverse orientation. Together with hesitation marks located on the neck and wrists these characteristics allowed to interpret this case as a suicide.