Reservations about likelihood ratios (and some other aspects of forensic ‘Bayesianism’)

The focus of the article is the application of modern Bayesianism in the context of forensic science, as advocated by many in England and Europe. The article reviews the many aspects of modern Bayesianism that extend well beyond the analytic truth of Bayes’s Theorem, and focuses, among other things, on the limits of what can be accomplished by the invocation of ‘subjective’ probabilities. In a sense, all probabilities are subjective, since they are all mind dependent. However, the important issue in forensic contexts, as in others, is not the subjective nature of invoked probabilities, but the characteristics of the belief warrant to be required for them in different decisional contexts.