Probability and Uncertainty in Law

Abstract

Uncertainty is a pervasive feature of law and legal systems. One important form of uncertainty in law is factual uncertainty. These lecture notes examine several strategies for portraying or dissecting this form of uncertainty. The relationship between legal uncertainty and factual uncertainty is discussed. Graphic representations of factual uncertainty are discussed. The complexity of real-world networks of inference in legal settings is discussed. The question of whether the complexity of real-world factual inference in legal settings outruns formal analysis is discussed. The notes consider that probability theorists have developed strategies for simplifying inference networks - partly or mainly for the purpose of preserving computational tractability. The suggestion is made that some of these strategies may not be appropriate for representing the types of factual and evidential uncertainty that often arise in legal settings.