Artistic enhancement in the production of photo-fit likenesses: An examination of its effectiveness in leading to suspect identification

Following a crime, witnesses are often asked by the police to construct a Photo-FIT likeness of the suspect. However, previous laboratory research has indicated that the quality of the likenesses produced can be very poor. This study investigated whether the artistic enhancement of the basic Photo-FIT by a skilled operator using a variety of techniques influenced the quality of the Photo-FIT impression produced, and in turn increased the likelihood of correct recognition from the Photo-FIT. Six professional police Photo-FIT operators produced one basic Photo-FIT which was not artistically enhanced in any way and one Photo-FIT which had been artistically enhanced. These two types of Photo-FIT were given to 105 police recruits who were required to identify which face that Photo-FIT represented from a photographic lineup of 12 ‘suspect’ photographs. Composites which had been enhanced were significantly more successful in leading to a correct identification than were basic composites which had not been enhanced. The implications of these findings for police procedure and practice in the employment of commercial composite systems are discussed.     

Firearm examination: Examiner judgments and computer‐based comparisons

Forensic firearm examination provides the court of law with information about the source of fired cartridge cases. We assessed the validity of source decisions of a computer‐based method and of 73 firearm examiners who compared breechface and firing pin impressions of 48 comparison sets. We also compared the computer‐based method's comparison scores with the examiners' degree‐of‐support judgments and assessed the validity of the latter. The true‐positive rate (sensitivity) and true‐negative rate (specificity) of the computer‐based method (for the comparison of both the breechface and firing pin impressions) were 94.4% and at least 91.7%, respectively. For the examiners, the true‐positive rate was at least 95.3% and the true‐negative rate was at least 86.2%. The validity of the source decisions improved when the evaluations of breechface and firing pin impressions were combined and for the examiners also when the perceived difficulty of the comparison decreased. The examiners were reluctant to provide source decisions for "difficult" comparisons even though their source decisions were mostly correct. The correlation between the computer‐based method's comparison scores and the examiners' degree‐of‐support judgments was low for the same‐source comparisons to negligible for the different‐source comparisons. Combining the outcomes of computer‐based methods with the judgments of examiners could increase the validity of firearm examinations. The examiners' numerical degree‐of‐support judgments for their source decisions were not well‐calibrated and showed clear signs of overconfidence. We suggest studying the merits of performance feedback to calibrate these judgments.     

Policy process perceptions of senior Canadian federal civil servants: a view of the state and its environment

Abstract: Based on interviews with senior civil federal civil servants in Ottawa, perceptions of various actors' influence on public policy are examined. It is hypothesized that perceived influence patterns will change as one moves across the major phases of the policy process. Although it is expected that actors within the state will be of primary importance throughout the process, it is also expected that the relative importance of actors outside the state will increase as one moves from forming a policy agenda and selecting policy towards policy implementation. This should be particularly true of the perceived influence of private companies. Despite this change in perceived levels of influence of state versus non-state actors, the structure of correlation patterns for perceived influence patterns will probably not change dramatically from one policy process phase to the next. Results are also presented pertaining to the actual interaction patterns of the civil servants who were interviewed, as well as the relation between interaction and perceived influence. It is expected that there will be positive relations between these two types of variables but that direct interaction will not consistently explain the majority of variation in perceived influence variables. Sommaire: À la suite d'entrevues avec des hauts fonctionnaires fédéraux à Ottawa, on examine ici les perceptions quant à l'influence de divers intervenants sur les politiques gouvernementales. On prend pour hypothèse que ces perceptions évolueront à mesure que l'on avance d'une grande étape à l'autre dans le processus de définition des politiques. On s'attend à ce que les intervenants étatiques jouent un rôle primordial tout au long du processus, mais aussi à ce que le rôle relatif des intervenants extérieurs au gouvernement prenne de l'ampleur lorsqu'on passe de l'établissement d'une liste de politiques au choix des politiques elles-mêmes et, en?fin, à la mise en oeuvre de ces politiques. Ceci devrait s'appliquer tout particulièrement à la manière dont on perçoit l'influence des sociétés privées. Malgré ce changement du niveau d'influence perçu entre les intervenants gouvernementaux et les nongouvernementaux, la structure corrélative des influences perçues ne changera probablement pas de façon dramatique d'une étape à l'autre du processus d'élaboration des politiques. On présente également des résultats concernant l'interaction effective des fonctionnaires interviewés, ainsi que le rapport entre cette interaction et l'influence perçue. On prévoit des rapports positifs entre ces deux groupes de variables, mais aussi que l'interaction directe ne saurait expliquer de manière cohérente la plupart des variations dans les variables de l'influence perçue.