Is Hindsight Really 20/20?: The Impact of Outcome Information on the Decision-Making Process

Previous research has reviewed the issue of biasability in forensic evaluation and has anecdotally related different forms of bias to forensic work; however, there is no empirical research that explores hindsight bias in forensic evaluation. Hindsight bias is the tendency for an individual to believe that a specific event, in hindsight, was more predictable than it was (in foresight). Using an international sample of 95 mental health professionals the current study explored the impact of outcome knowledge on the decision-making process in forensic evaluation. Using a 2 (suicide/self-harm v. homicide/other-harm) x 2 (outcome provided v. no outcome provided) between groups design, participants reviewed a hypothetical patient’s hospital chart and then indicated their opinion regarding the risk of harm the patient presented to self or others. Participants provided with outcome information were significantly more likely to indicate that they would have predicted the outcome than those who were not provided with outcome information. In addition, participants with outcome information endorsed higher risk ratings for violence than those who were not provided with outcome information, suggesting that context can impact the way in which information is perceived. Thus, participant’s evaluation of and decision-making about an event, in hindsight, may not meet the objective standard to which forensic mental health professionals aspire. The importance of recognizing and understanding this form of bias and its limitations as well as appropriate techniques to reduce biases and achieve a better quality of work are discussed.