The values of prediction in criminal cases

Like scientists, investigators and decision-makers in criminal cases both explain known evidence and use the resulting explanations to make novel predictions. Philosophers of science have made much of this distinction, arguing that hypotheses which lead to successful predictions are—all else being equal—epistemically superior to those that merely explain known data. Their ideas also offer important lessons for criminal evidence scholarship. This article distinguishes three values of prediction over explaining known facts in criminal cases. First, witnesses who predict are—all else being equal—more reliable than those who do not because they are less likely to be biased or lying. Second, investigators who only explain known facts run the risk of ‘fudging’ the scenarios that they formulate. Predictions can protect us against this danger. Third, carefully constructed predictions may help investigators to avoid confirmation bias. This article ends with a case study of the murder of Hae Min Lee.