Image analysis of gunshot residue on entry wounds. II--A statistical estimation of firing range.

A statistical investigation of the relationship between firing range and the amount and distribution of gunshot residue (GSR), used automated image analysis (IA) to quantify GSR deposit resulting from firings into pig skin, from distances ranging between contact and 45 cm. Overall, for a Ruger .22 semi-automatic rifle using CCI solid point, high velocity ammunition, the total area of GSR deposit on the skin sections decreased in a non-linear fashion with firing range. More specifically there were significant differences in the amount of GSR deposited from shots fired at contact compared with shots fired from distances between 2.5 and 45 cm; and between shots fired from a distance of 20 cm or less, with shots fired at a distance of 30 cm or more. In addition, GSR particles were heavily concentrated in the wound tract only for contact and close range shots at 2.5 cm, while the particle distribution was more uniform between the wound tract and the skin surfaces for shots fired from distances greater than 2.5 cm. Consequently, for future scientific investigations of gunshot fatalities, once standards have been established for the weapon and ammunition type in question, image analysis quantification of GSR deposited in and around the gunshot wound may be capable of providing a reliable, statistical basis for estimating firing range.     

Fatality caused by a combined trimipramine-citalopram intoxication

A 53-year-old woman who was diagnosed as suffering from depression was found dead in her bed. The autopsy revealed no morphological changes sufficient to explain death. Toxicological analysis was performed and the drugs trimipramine (2.33 mg/l), citalopram (4.81 mg/l) and zolpidem (0.07 mg/l) were identified in the femoral blood. A combined drug intoxication resulting in synergistic effects to cardiovascular disorders was proposed as the cause of death. An acute overdose and suicide was suggested by calculation of the parent drug to main metabolite ratios in femoral blood and liver tissue. The trimipramine to desmethyltrimipramine ratios were calculated to be 2.06 and 3.18, the citalopram to desmethylcitalopram ratios were 1.96 and 2.02.     

Assessing Stability and Change in Criminal Offending: A Comparison of Random Effects, Semiparametric, and Fixed Effects Modeling Strategies

An important theoretical problem for criminologists is an explanation forthe robust positive correlation between prior and future criminaloffending. Nagin and Paternoster (1991) have suggested that the correlationcould be due to time-stable population differences in the underlyingproneness to commit crimes (population heterogeneity) and/or thecriminogenic effect that crime has on social bonds, conventionalattachments, and the like (state dependence). Because of data andmeasurement limitations, the disentangling of population heterogeneityand state dependence requires that researchers control for unmeasuredpersistent heterogeneity. Frequently, random effects probit models havebeen employed, which, while user-friendly, make a strong parametricassumption that the unobserved heterogeneity in the population follows anormal distribution. Although semiparametric alternatives to the randomeffects probit model have recently appeared in the literature to avoid thisproblem, in this paper we return to reconsider the fully parametric model. Viasimulation evidence, we first show that the random effects probit modelproduces biased estimates as the departure of heterogeneity from normalitybecomes more substantial. Using the 1958 Philadelphia cohort data, we thencompare the results from a random effects probit model with a semiparametricprobit model and a fixed effects logit model that makes no assumptions aboutthe distribution of unobserved heterogeneity. We found that with this dataset all three models converged on the same substantive result—evenafter controlling for unobserved persistent heterogeneity, with models thattreat the unobserved heterogeneity very differently, prior conduct had apronounced effect on subsequent offending. These results are inconsistentwith a model that attributes all of the positive correlation between priorand future offending to differences in criminal propensity. Sinceresearchers will often be completely blind with respect to the tenabilityof the normality assumption, we conclude that different estimationstrategies should be brought to bear on the data.     

Reforming rural Ontario

Abstract: This paper turns the scholarly spotlight onto an overlooked aspect of the Ontario municipal system by exploring the issue of county government reform in four selected communities in southern Ontario. Various proposals for county government reform have been advanced by the provincial government during the last quarter-century; here we consider the “common sense” approach to municipal government reform adopted by the Harris government after its election in 1995. We analyse how four counties have responded to this concerted and forceful attempt to bring about major county restructuring. The study has two major objectives. First, it illustrates the forces that have at once advanced and constrained county government reform in recent years; second, it attempts to explain major differences in the manner in which individual counties have responded to the Harris government's drive for reform. Finally, the paper concludes with some reflections on the viability of rural government in Ontario in the light of the substance and process of county government reform. Sommaire: Cet article examine un aspect négligé du système municipal ontarien en explorant la question de la réforme des gouvernements de comté dans quatre communautés choisies du sud de l'Ontario. Le gouvernement provincial a fait diverses propositions de réforme du gouvemement de comté au cours du demier quart de siècle; ici, nous examinons l'approche basée sur le « ban sens » adoptée par le gouvernement Harris en ce qui concerne les gouvernements municipaux, après son élection en 1995, et nous analysons la manière dont quatre comtés ont réagi à cette tentative concertée et vigoureuse de déclencher une forte restructuration au niveau du comté. Cette étude a deux grands objectifs. Premièrement, elle illustre les forces qui ont à la fois promu et retenu la réforme des gouvernements de comté au cours de ces dernières annèes; deuxièmement, elle essaie d'expliquer les principaux écarts dans la façon dont chaque comté a réagi aux efforts de réforme du gouvemement Harris. Enfin, I'article offer quelques réflexions sur la viabilité du gouvernement rural en Ontario à la lumière du fond et du processus de réforme des gouvernements de comté.