Mitigating risks of overreliance on information at the crime scene

Data on the effectiveness of previous casework decisions can support Scene of Crime Officers (SoCOs) in making complex and rapid decisions during a crime scene investigation. This data is known to influence SoCOs' decision-making, for example, when selecting locations with high success rates for DNA analysis. At the same time, overreliance on this information may diminish the use of their own professional experience, highlighting the need for measures that promote a balanced integration of information sources and to mitigate potential cognitive biases. This study examines (1) the effect of receiving a warning about cognitive biases prior to information provision; (2) the effect of receiving information after an initial trace collection based on experience; and (3) how participants reflect on their use of the provided information and on the methods used to counteract overreliance on it. The results show that receiving a warning has no significant effect on the influence of the provided information. Promising results were observed for participants who received the information after an initial trace collection: they collected traces based on both experience and the provided information on DNA success rates. These participants were also more aware of their use of the provided information and its potential influence on their decision-making. Overall, the findings show tangible effects of providing and using scientific information in forensic decision-making while ensuring that the beneficial effect of professional experience is not compromised.