Simulations of child sexual abuse interviews using avatars paired with feedback improves interview quality

We tested whether simulated child sexual abuse (CSA) interviews with computer-generated child avatars could improve interview quality. Feedback was provided not only on question types, as in previous research, but also on whether the conclusions drawn by the interviewers were correct. Twenty-one psychology students (average age M = 24.5) interviewed four different avatars which had a simulated story of either abuse or non-abuse. The participants were randomly divided into two groups: one received feedback on question types and conclusions after each simulated interview and the other one did not receive any feedback. Avatars revealed pre-defined ‘memories’ as a function of algorithms formulated based on previous empirical research on children's suggestibility. The feedback group used more open-ended and fewer closed questions. They also made more correct conclusions and found more correct details in the last two interviews compared to the no-feedback group. Feedback on both the question types and conclusions in simulated CSA interviews with avatars can improve the quality of investigative interviews in only one hour. The implications for training practice were discussed.     

BK virus genotype distribution offers information of tracing the geographical origins of unidentified cadaver

There are no efficient methods to determine the geographic origin of unidentified cadavers. We showed earlier that the geographical distribution of the JC virus genotype detected from human kidneys indicates the host's geographical origin. As there are still cadavers from which we cannot detect the JC virus (JCV), we investigated whether the genotype of another virus species belonging to the same family, human BK virus (BKV), could also be used to detect human geographical origin. BKV was found in 11 of 36 cases (30.5%). Even in the seven JCV-negative cases, the host's geographic origin could be estimated from the BKV genotype. Four subjects were positive for both the BKV and JCV. As the distribution areas of BKV and JCV genotypes are not identical, it is possible to narrow down the geographic area that any cadaver originates from.     

Testing the utility of a geographical profiling approach in three rape series of a single offender: a case study

The purpose of the study was to test the potential utility of a geographical profiling approach for three separate series of rapes committed by a single offender. Two different mathematical distance-decay functions using either a normal distribution with a mean distance and standard deviation based on previous research or a truncated negative exponential function based on distances between crime sites in the series under investigation were applied to each of the series giving prioritised search areas the accuracy of which was then assessed. The prioritised area that had to be searched before the home base of the offender could be located varied from 7.60 km(2) or 2.15% of the total search area at its best to 15 1.10 km(2) or 42.66% at its worst for the normal distribution based on previous research and from 42.06 km(2) or 11.88% to no improvement when the truncated negative exponential function was used. The functions used showed less predictive ability when the offender was a commuter. Explanations for the variations in the findings as well as suggestions for improvements were outlined in the discussion.     

Judgment of age and attractiveness in a paired comparison task: Testing a picture set developed for diagnosing paedophilia

Purpose. The Not‐Real‐People picture set serves as stimulus material for assessing paedophilic sexual interest. The pictures were generated according to five stages of sexual maturation from infancy to adulthood. While experts seem to be able to discern between the pictures based on maturity levels for a nude variant of the stimuli, it remained unclear whether lay persons would be able to reliably distinguish between picture of clothed individuals from various maturity levels. Methods. Heterosexual university students (52 females, 50 males) participated in a paired comparison task, deciding which of the persons shown on two pictures was younger and which one was more attractive. Additionally, reaction times were recorded. Results. Both male and female judges were able to differentiate between stimuli from the opposite sex with regard to age: the perception of the stages of pubertal development conformed to a measurement on a ratio scale. Similarly, the decisions on attractiveness of the categories were in accordance with a ratio scale. Male participants favoured adolescent and adult female stimuli. Contrary to expectation, female participants did not show a preference for any single age category. Conclusions. The stimuli appear suitable for diagnostic purposes. The participants' decisions reflect the inherent maturity levels of the persons depicted. Reaction times in the paired comparison paradigm increase with task difficulty (i.e., similitude of pictures). The implications for indirect measures of sexual interest, based on reaction times, are discussed.     

Predicting presence of offender's criminal record from antisocial lifestyle indicators of homicide victims

The aim of the present study is to explore the possibility of predicting the presence of a criminal record in the background of a homicide offender on the basis of victim characteristics. Eight victim characteristics, as well as the presence or absence of offender criminal record and offender violent criminal record, were coded for 502 Finnish homicides. A configural frequency analysis (CFA) showed that it was possible to predict the presence of a criminal record on the basis of the victim variables. The practical significance of the results for police investigations is discussed.     

Predicting offender home location in urban burglary series

Residential location of a criminal can be predicted statistically [M. Laukkanen, P. Santtila, Predicting the home location of a serial commercial robber, Forensic Sci. Int. 157 (2006) 71-82]. Examined were: accuracy of the technique for urban burglary series, correlations between way of committing burglary and distance and use of those correlations in enhancing prediction accuracy. Data: 78 residential burglary series from Greater Helsinki area, Finland. Series for which the home location prediction was made was never part of the predicting model. Distances between home and crime-site were short (Mdn 3.88km; IQR=1.16-10.10km). Search area of a perpetrator could be limited to 1.95% (Mdn, IQR=0.64-18.70%) of the total study area. For series which conformed to Circle Hypothesis (45%), search area was 0.84% (Mdn, IQR=0.51-2.34%). Correlations between crime features and distance were found to enhance accuracy when features of series hinted short distance: sub-model limited search area to 0.19% (Mdn, IQR=0.07-0.65%).     

Assessment of sexual interest using a choice reaction time task and priming: A feasibility study

Purpose. We investigated the feasibility of assessing sexual interest in hetero‐ and homosexual men using two information‐processing methods, namely a choice reaction time task and priming. The participants were expected to have longer reaction times for sexually explicit when compared with non‐explicit pictures due to sexual content‐induced delay. In addition, the reaction times of the heterosexual (N=15) and homosexual (N=11) men for pictures corresponding with their sexual interest were compared to pictures not corresponding with their sexual interest. Heterosexual men were expected to have longer reaction times during the presentation of sexually explicit female as opposed to male pictures, whereas homosexual men were expected to have the opposite pattern. Method. The participants were presented either sexually explicit or non‐explicit male and female target pictures (and primes that preceded the targets in random combinations) while simultaneously performing a choice reaction time task in three phases each containing a total of 160 prime–target pairs. Results. Both expectations were confirmed in phase 1 of the study. In phase 2, the means differed in the expected way, but the effects were not significant. In phase 3, the expected effect was moderated by a complex priming effect. Conclusions. The results suggest that the choice reaction time task is a promising way of measuring sexual interest but that questions of habituation should be given more attention in future studies.     

Tasks of research in forensic medicine - different study types in clinical research and forensic medicine

In the last years the research output of forensic medicine has sometimes been regarded as insufficient and as of poor quality, especially when parameters as impact factors and external funding were taken into account. However, forensic medicine has different tasks compared to clinical medicine. The main difference between basic subjects, clinical and forensic medicine is not a lack of scientific efficiency in forensic medicine but is a result of the questions asked, the available methods and specific aims. In contrast to natural-scientific research, forensic science has furthermore important intersections with arts and socio-scientific disciplines. Etiologic and pathogenetic research is of only limited relevance in forensic medicine. Thus, forensic medicine is excluded from these research fields, which are mainly supported by external funding. In forensic medicine research mainly means applied research regarding findings, the probative value and reconstruction as well as examination at different points of intersection between medicine and law. Clinical types of research such as controlled randomised, prospective cross-sectional, cohort or case-control studies can only rarely be applied in forensic medicine due to the area specific research fields (e.g. thantatology, violent death, vitality, traffic medicine, analytical toxicology, hemogenetics and stain analysis). The types of studies which are successfully established in forensic medicine are comparison of methods, sensitivity studies, validation of methods, kinetic examinations etc. Tasks of research in forensic medicine and study types, which may be applied will be addressed.