The identification of individuals by observational gait analysis using closed circuit television footage

This study investigated the ability of individuals with experience in gait analysis to identify people by observing features of gait recorded by closed circuit television cameras (CCTV). Seven experienced analysts each viewed five samples of footage. Each sample showed a “target walker” and five “suspect walkers.” The task of the experienced analysts was to determine which, if any, of the “suspect walkers” was the “target walker.” All of the participant “walkers” wore identical loose fitting clothing to mask anatomical and body contour features, and balaclavas to obscure facial features. The overall results showed that the experienced analysts made a correct decision in 124 of 175 cases (71%), significantly better than would have been expected to have occurred by chance (p < 0.05). A significant variation in correct decisions (p < 0.05) was shown to occur between the various angles from which the footage was recorded, footage recorded in the saggital plane showing the highest number of correct decisions. Significantly more correct decisions (p < 0.05) were also shown to occur when the footage of the “target walker” and that of the “suspect walker” were taken from the same angle. The results suggest that individuals with experience in gait analysis perform well in the comparative identification of suspects from CCTV footage, and therefore do have a role to play as expert witnesses in this field.     

Child molestation and psychopathy: a taxometric analysis

ABSTRACT

Prior taxometric research on child molesters and general sex offenders has produced inconsistent and contradictory results. There are theoretical, practical, and policy reasons, however, to assume that a psychopathy taxon may exist in sex offenders and that a taxometric study might shed light on this issue. The mean above minus below a cut (MAMBAC), maximum covariance (MAXCOV), and latent-mode factor analysis (L-Mode) taxometric procedures were employed in three overlapping samples: 188 sex offenders with non-relative child victims, 555 sex offenders with non-relative child or adolescent victims or child incest victims, and a mixed sample of 1404 sex offenders. The taxometric analyses revealed evidence of continuous latent structure in all three samples. These results suggest that psychopathy in sex offenders, child molesters in particular, is organised quantitatively (continuous) rather than qualitatively (categorical).     

Online child exploitation: Challenges and future research directions

Given the relatively new phenomenon of online child exploitation – an important area of criminological and policy concern – it is difficult to obtain long term trend data on reported convictions. Existing legislative and prosecution-based approaches, while important, are unlikely to be adequate. This analysis of the legislative and prosecution-based responses in five Commonwealth countries (Australia, Canada, New Zealand, South Africa and United Kingdom), highlights the need for clear national and international definitions as the lack of consistency in the international legislative environment creates opportunities for sexual exploitation of children. To provide a multi-faceted and non-prosecutorial approach to address online child exploitation including the commercial exploitation of children, this paper identifies five potential research questions.