Highlights•Crime scene investigations are accompanied by cognitive challenges.•Introducing technologies at crime scenes requires research into the human factor.•Mobile technologies can impede the investigation without studying the impact.
Crime scene investigations are highly complex environments that require the CSI to engage in complex decision-making. CSIs must rely on personal experience, context information, and scientific knowledge about the fundamental principles of forensic science to both find and correctly interpret ambiguous traces and accurately reconstruct a scene. Differences in CSI decision making can arise in multiple stages of a crime scene investigation. Given its crucial role in forensic investigation, CSI decision-making must be further studied to understand how differences may arise during the stages of a crime scene investigation. The following exploratory research project is a first step at comparing how crime scene investigations of violent robberies are conducted between 25 crime scene investigators from nine countries across the world.Through a mock crime scene and semi-structured interview, we observed that CSIs have adopted a variety of investigation approaches. The results show that CSIs have different working strategies and make different decisions when it comes to the construction of relevant hypotheses, their search strategy, and the collection of traces. These different decisions may, amongst other factors, be due to the use of prior information, a CSI’s knowledge and experience, and the perceived goal of their investigation. We suggest the development of more practical guidelines to aid CSIs through a hypothetico-deductive reasoning process, where (a) CSIs are supported in the correct use of contextual information, (b) outside knowledge and expertise are integrated into this process, and (c) CSIs are guided in the evaluation of the utility of their traces.
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Forensic and behavioural science are often seen as two different disciplines. However, there is a growing realization that the two disciplines should be more strongly integrated. Incorporating psychological theories on human behaviour in forensic science could help solving investigative problems, especially at the crime scene. At the crime scene it is not just about applying scientific methods to analyse traces; these traces must first be perceived and categorized as relevant. At the crime scene, the behavioural perspective of an investigative psychologist could play an important role. In this study, we examine to what extent (1) investigative psychologists detect deviant behavioural cues compared to forensic examiners when investigating a crime scene, (2) forensic examiners can find the relevant traces that can be associated with this behaviour and (3) the availability of a psychological report highlighting these behavioural cues helps forensic examiners in finding more relevant traces. To this end, a total of 14 investigative psychologists and 40 forensic examiners investigated a virtual 3D mock crime scene. The results of this study show that investigative psychologists see significantly more deviant behavioural cues than forensic examiners, and that forensic examiners who receive a psychological report on these cues recognize and collect significantly more traces that can be linked to deviant behaviour and have a high evidential value than examiners who did not receive this information. However, the study also demonstrates that behavioural information is likely to be ignored when it contradicts existing beliefs.
Every year the police are confronted with an ever increasing number of complex cases involving missing persons. About 100 people are reported missing every year in the Netherlands, of which, an unknown number become victims of crime, and presumed buried in clandestine graves. Similarly, according to NWVA, several dead animals are also often buried illegally in clandestine graves in farm lands, which may result in the spread of diseases that have significant consequences to other animals and humans in general. Forensic investigators from both the national police (NP) and NWVA are often confronted with a dilemma: speed versus carefulness and precision. However, the current forensic investigation process of identifying and localizing clandestine graves are often labor intensive, time consuming and employ classical techniques, such as walking sticks and dogs (Police), which are not effective. Therefore, there is an urgent request from the forensic investigators to develop a new method to detect and localize clandestine graves quickly, efficiently and effectively. In this project, together with practitioners, knowledge institutes, SMEs and Field labs, practical research will be carried out to devise a new forensic investigation process to identify clandestine graves using an autonomous Crime Scene Investigative (CSI) drone. The new work process will exploit the newly adopted EU-wide drone regulation that relaxes a number of previously imposed flight restrictions. Moreover, it will effectively optimize the available drone and perception technologies in order to achieve the desired functionality, performance and operational safety in detecting/localizing clandestine graves autonomously. The proposed method will be demonstrated and validated in practical operational environments. This project will also make a demonstrable contribution to the renewal of higher professional education. The police and NVWA will be equipped with operating procedures, legislative knowledge, skills and technological expertise needed to effectively and efficiently performed their forensic investigations.
In het forensisch werkveld staan drie vragen centraal. Het gaat dan om “wie is het”, “wat is er gebeurd” en “wanneer is het gebeurd”. Alle informatie die bijdraagt aan het beantwoorden van deze vragen is waardevol in zaakonderzoeken. Vaak wordt er wel een biologisch spoor gevonden, maar is er geen “match” met de databank. In dit geval kan profileringsinformatie helpen bij het zoeken naar de juiste persoon. Met profilering wordt hier bedoeld een serie stoffen, ook markers genoemd, die informatie geven over de levensstijl van mensen. De levensstijl kan bestaan uit kenmerken, voeding, gewoonten en activiteiten. Een recent voorbeeld van een profileringsmethode is het analyseren van de buitenzijde van mobiele telefoons. Door het hanteren van de telefoon laten mensen zweet en stoffen achter die gekarakteriseerd kunnen worden. Het profiel van deze stoffen geeft een beschrijving van de levensstijl van de eigenaar. In veel zaken zijn er echter geen mobiele telefoon aanwezig, maar wel andere sporen zoals haar. Daarom is er behoefte aan een methode om haar te gebruiken voor profilering. Bovendien geeft haar een indicatie van tijd en gebeurtenissen uit het verleden omdat het langzaam groeit. In principe kan er dan informatie over de drie vragen (wie, wat, wanneer) verzameld worden. Haren worden op dit moment vooral gebruikt voor het meten van drugs, alcohol gebruik, cortisol en nicotine. Er is echter behoefte aan een breder palet van stoffen dat in één keer in haar kan worden gemeten. Het doel van dit onderzoek is daarom het ontwikkelen van een methode waarmee in één analysegang een profiel van circa 15 uiteenlopende markers kan worden gemeten.
