The likelihood approach to compare populations: a study on DNA evidence and pitfalls of intuitions

The paper follows on from earlier work [Taroni F and Aitken CGG. Probabilistic reasoning in the law, Part 1: assessment of probabilities and explanation of the value of DNA evidence. Science & Justice 1998; 38: 165-177]. Different explanations of the value of DNA evidence were presented to students from two schools of forensic science and to members of fifteen laboratories all around the world. The responses were divided into two groups; those which came from a school or laboratory identified as Bayesian and those which came from a school or laboratory identified as non-Bayesian. The paper analyses these responses using a likelihood approach. This approach is more consistent with a Bayesian analysis than one based on a frequentist approach, as was reported by Taroni F and Aitken CGG. [Probabilistic reasoning in the law, Part 1: assessment of probabilities and explanation of the value of DNA evidence] in Science & Justice 1998.     

IMMIGRATION AND THE RECENT VIOLENT CRIME DROP IN THE UNITED STATES: A POOLED,CROSS‐SECTIONAL TIME‐SERIES ANALYSIS OF METROPOLITAN AREAS*

A good deal of research in recent years has revisited the relationship between immigration and violent crime. Various scholars have suggested that, contrary to the claims of the classic Chicago School, large immigrant populations might be associated with lower rather than higher rates of criminal violence. A limitation of the research in this area is that it has been based largely on cross‐sectional analyses for a restricted range of geographic areas. Using time‐series techniques and annual data for metropolitan areas over the 1994–2004 period, we assess the impact of changes in immigration on changes in violent crime rates. The findings of multivariate analyses indicate that violent crime rates tended to decrease as metropolitan areas experienced gains in their concentration of immigrants. This inverse relationship is especially robust for the offense of robbery. Overall, our results support the hypothesis that the broad reductions in violent crime during recent years are partially attributable to increases in immigration.     

Evidence for Connections Between Prosecutor-Reported Marijuana Case Dispositions and Community Youth Marijuana-Related Attitudes and Behaviors

This article examines relationships between local drug policy (as represented by prosecutor-reported case outcomes for first-offender juvenile marijuana possession cases) and youth self-reported marijuana use, perceived risk, and disapproval. Interviews with prosecutors and surveys of 8th-, 10th-, and 12th-grade students in the United States were conducted in 2000. Analyses include data from 97 prosecutors and students from 127 schools in 40 states. Results indicate significant relationships between local drug policy and youth marijuana use and attitudes. In general, more-severe dispositions are associated with less marijuana use, higher disapproval rates, and increased perceptions of great risk. Associations primarily appear to be specific to marijuana-related outcomes. Results are discussed within the framework of both deterrence and broader social norms regarding substance use.     

Methods of Choice in Completed Suicides: Gender Differences and Review of Literature

Abstract:  Suicide is an important public health hazard worldwide. A 4-year retrospective study from January 2000 to December 2003 was conducted to identify the favored methods in realized suicides among males and females in the west coastal region of India. During the study period, a total of 539 cases of suicidal deaths were autopsied. Males were predominantly affected (male: female—1.9:1). The age of the victims ranged from 13 to 90 years in males (mean = 40.1 years, median = 37.0 years) and 15 to 85 years in females (mean = 36.6 years, median = 32.0 years). Most favored method of suicide amongst males and females was hanging (36.9%, n  = 199) followed by poisoning (34.7%, n  = 187). Male dominance was apparent for each method of suicide except for self-immolation. Males were relatively more likely to use hanging and poisoning while females were more likely to prefer drowning and self-immolation as methods of suicide. Relatively younger females (mean   = 33.0 years, median = 32.0 years) preferred hanging as a method of suicide when compared to males (mean = 42.4 years, median = 40.0 years). Among females, significantly younger females resorted to hanging when compared to older females who preferred drowning. On investigating the various theories proposed for choice of suicide methods in males and females in different regions we conclude that preference of method of suicide in men and women is complexly determined. In this region, availability, accessibility, popularity, and socioacceptability seem to be the major determinants in the choice of methods among males and females rather than violence associated and lethality of the method. Females were as likely to use lethal and violent methods as males in this region.     

Walk and Die: An Unusual Presentation of Head Injury

Abstract:  We report three deaths in young adult males following closed blunt trauma to the head and face where the affected individuals were able to walk away from the incident, before subsequently collapsing and dying a short distance from the site of the assault. In each case, due to the rapidity of the posttrauma collapse, the pathologist was faced with a diagnostic difficulty at autopsy; the external examination revealed multiple injuries to the head and face, but internal examinations showed limited findings with no structural explanation for the death. We discuss possible mechanisms that could account for this scenario, the implications of alcohol consumption with a concussive head injury, and parallels that can be drawn with the so-called "talk and die,""talk and deteriorate," and "second impact syndrome." Finally, the possible role of so-called "postexercise peril" is discussed in relation to these deaths.     

Effects of advanced age and dementia on restoration of competence to stand trial

Elderly defendants (age 65+) and defendants with dementia adjudicated incompetent to stand trial and hospitalized for restoration to competence (RTC) often present unique challenges to clinicians charged with their restoration. In this study, we attempted to better identify predictors of successful RTC by building upon previous research correlating increased age with decreased likelihood of RTC. We identified elderly non-demented defendants (n = 31) and defendants diagnosed with dementia (n = 47) from a state database of 1380 individuals hospitalized for competence restoration from 1988–2004. Using regression analysis and correcting for demographic variables and common admission psychiatric diagnoses, we studied the relationship of age at hospital admission and dementia diagnosis on the likelihood of successful RTC. Both advanced age and dementia diagnosis were associated with decreased RTC. After correcting for dementia diagnosis, increased age retained its negative correlation with restoration success. Both elderly non-demented defendants and defendants diagnosed with dementia were significantly less likely to be restored to competence than all other RTC admissions (n = 1302). However, a substantial percentage of both demented and elderly non-demented defendants were successfully restored to competence, potentially justifying restoration attempts for both of these groups of defendants.