The subject of this thesis is reasoning with evidence to establish the facts in criminal cases. In al legal context, the study of evidence is often equated with the study of the "law of evidence", for example, the legal rules of evidence that govern which types of evidence are legally valid or admissible. However, a large part of the study of evidence constitutes the study of the "rational process of proof, which concerns the facts of the case rather than the legal specifics. The reasoning in the process of proof, which is discussed in chapter 2, involves constructing, testing and justifying comp0lex hypotheses about what happened in a case using evidence (e.g. witness statements, tangible evidence such as a knife or blood) and general commonsense knowledge (e.g. generalizations such as 'witnesses under oath usual human behaviour).