Intelligent indexing of crime scene photographs

The Scene of Crime Information System's automatic image-indexing prototype goes beyond extracting keywords and syntactic relations from captions. The semantic information it gathers gives investigators an intuitive, accurate way to search a database of cases for specific photographic evidence. Intelligent, automatic indexing and retrieval of crime scene photographs is one of the main functions of SOCIS, our research prototype developed within the Scene of Crime Information System project. The prototype, now in its final development and evaluation phase, applies advanced natural language processing techniques to text-based image indexing and retrieval to tackle crime investigation needs effectively and efficiently

Minimum Education Requirements for Crime Scene Investigators

The initial crime scene investigation is critical since it is the primary step in the investigative process; therefore, individuals assigned to process a scene should be highly educated. Improperly educated (or uneducated) crime scene investigators (CSIs) can mishandle evidence during an investigation, affecting the outcome of cases. The minimum education requirement for CSIs should transition from a high school diploma—the current requirement—toward a bachelor’s degree. The importance of acquiring a college-level education is observed in a study conducted on crime scene examiners in Australia. To determine the educational requirement for CSIs in the United States, information was gathered electronically from numerous law enforcement departments. The most common entry-level education was a high school diploma, followed by an associate’s degree, and lastly, a bachelor’s degree. A bachelor’s degree, with coursework specifically intended for individuals not wanting to work in a laboratory, will ensure CSIs are well equipped to correctly perform their duties

The Utilization of Mobile Technology for Crime Scene Investigation in the San Francisco Bay Area

The research presented aims to explore factors affecting the decision to adopt a mobile crime scene investigation application in police departments throughout the San Francisco Bay Area. To accomplish this goal, the mobile technology acceptance model was used in designing a survey for data collection. This model utilizes four categories to interpret the factors that influence a police officer’s decision to accept or reject mobile technologies: performance, security and reliability, management style, and cognitive acceptance. Nine police departments were sampled through a series of in-person and over-the-phone interviews to obtain data regarding factors affecting the adoption of a mobile crime scene investigation application. Results suggest that if a mobile crime scene investigation application were made available, a vast majority of the police departments in the Bay Area would implement this new technology

Behavioural case linkage : linking residential burglary offences in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Albany, New Zealand

This thesis aims to replicate and extend prior research on behavioural case linkage from the United Kingdom and Finland, using a sample of residential burglaries committed in New Zealand. Eighty-two solved residential burglaries, committed by 47 serial burglary offenders in Napier, New Zealand, are sampled from the New Zealand Police National Intelligence Application (NIA) database. Prior research using behavioural case linkage for residential burglary has found support for the usefulness of crime scene behaviours, inter-crime distance and temporal proximity to accurately predict offences committed by the same offender. Inter-crime distance has consistently shown higher degrees of accuracy in determining whether two crimes are linked to the same offender. Using the methodology followed by previous researchers, 41 linked crime pairs (two offences committed by the same offender) and 41 unlinked crime pairs (two offences committed by different offenders) are created. Three behavioural domains of crime scene behaviours, inter-crime distance and temporal proximity of offences committed by the same offender are compared with offences committed by different offenders. Logistic regression analysis and receiver operating curve (ROC) analysis is used to determine the ability of the three behavioural domains to accurately predict whether offences are linked or not. Similar to prior studies, all three behavioural domains showed moderate predictive ability in reliably determining the linked status of crime pairs. Contrary to prior studies inter-crime distance was found to be the least accurate predictor in determining the linked status of crime pairs, with an optimal model combining temporal proximity with crime scene behaviours showing the greatest degree in determining whether crimes were committed by the same offender or not. These results provide support for the use of behavioural case linkage for linking residential burglary offences in New Zealand while caution is required when relying on inter-crime distance alone as a linking feature within small geographic areas

Levels and Variations of Violation in Rape.

This chapter investigates the variations in crime scene behaviour revealed in a sample of victim statements in cases of stranger sexual assault. Building on previous findings by Canter and Heritage (1990), and Canter (1994), it was hypothesised that there existed a scale of differing levels of violation by the offender. This scale, based upon actions in the offence, ranged from personal violation, through to physical violation and finally, at the most extreme level, sexual violation. Offences could also be differentiated at the personal and physical levels in terms of hostile, controlling, stealing or involving thematic emphases to the criminal’s actions. To test these hypotheses, crime scene data from the first detected offences of 112 British rapists were analysed using a multi-dimensional scaling procedure to explore the relationships amongst crime scene actions. The results provided empirical support for the four action themes as different expressions of various intensities of violation. The implications that these findings have for the investigation of stranger sexual assault and treatment of victims are discussed

Crime scene examiners and volume crime investigations: an empirical study of perception and practice

Most police forces in the UK employ specially trained crime scene examiners (CSEs) to provide forensic science support to the investigation of crime. Previous research has shown wide variations in the management, deployment, and performance of this staff group. There is also evidence that informal elements of professional and organisational culture, in particular the role characterisations of crime scene examiners, also have a bearing on their effective use in the investigation of high volume property crime. These issues are explored as part of a more extensive study of forensic science provision in the two largest police forces in Scotland and by the four main Scottish Police Services Authority Forensic Services (SPSA FS) units. A range of staff in these organisations described their understandings of the role of crime scene examiners – as evidence collectors, forensic investigators, specialist advisers, or any combination of these. Whilst two thirds (62%) of respondents recognised the complexity and scope of the role of CSEs including its cognitive elements, a substantial minority (38%) categorised the role as having a single element – collecting evidence – and therefore perceived it as limited largely mechanical in character. The reasons for, and consequences of, this perception are considered, and the paper concludes with a challenge to reconsider this limited view of what crime scene examiners can contribute to volume crime investigations

SOME FORENSIC ASPECTS OF BALLISTIC IMAGING

Analysis of ballistics evidence (spent cartridge casings and bullets) has been a staple of forensic criminal investigation for almost a century. Computer-assisted databases of images of ballistics evidence have been used since the mid-1980s to help search for potential matches between pieces of evidence. In this article, we draw on the 2008 National Research Council Report Ballistic Imaging to assess the state of ballistic imaging technology. In particular, we discuss the feasibility of creating a national reference ballistic imaging database (RBID) from test-fires of all newly manufactured or imported firearms. A national RBID might aid in using crime scene ballistic evidence to generate investigative leads to a crime gun’s point of sale. We conclude that a national RBID is not feasible at this time, primarily because existing imaging methodologies have insufficient discriminatory power. We also examine the emerging technology of micro- stamping for forensic identification purposes: etching a known identifier on firearm or ammunition parts so that they can be directly read and recovered from crime scene evidence. Microstamping could provide a stronger basis for identification based on ballistic evidence than the status quo, but substantial further research is needed to thoroughly assess its practical viability

Rapid identification information and its influence on the perceived clues at a crime scene:an experimental study

Crime scenes can always be explained in multiple ways. Traces alone do not provide enough information to infer a whole series of events that has taken place; they only provide clues for these inferences. CSIs need additional information to be able to interpret observed traces. In the near future, a new source of information that could help to interpret a crime scene and testing hypotheses will become available with the advent of rapid identification techniques. A previous study with CSIs demonstrated that this information had an influence on the interpretation of the crime scene, yet it is still unknown what exact information was used for this interpretation and for the construction of their scenario. The present study builds on this study and gains more insight into (1) the exact investigative and forensic information that was used by CSIs to construct their scenario, (2) the inferences drawn from this information, and (3) the kind of evidence that was selected at the crime scene to (dis)prove this scenario. We asked 48 CSIs to investigate a potential murder crime scene on the computer and explicate what information they used to construct a scenario and to select traces for analysis. The results show that the introduction of rapid ID information at the start of an investigation contributes to the recognition of different clues at the crime scene, but also to different interpretations of identical information, depending on the kind of information available and the scenario one has in mind. Furthermore, not all relevant traces were recognized, showing that important information can be missed during the investigation. In this study, accurate crime scenarios where mainly build with forensic information, but we should be aware of the fact that crime scenes are always contaminated with unrelated traces and thus be cautious of the power of rapid ID at the crime scene