Legal Probability and Statistics

in the Chair] SUMMARY A classification of legal cases, in which the statistician may be involved as an expert witness, is proposed. Examples of each type of case are given. In most cases, probability theory and statistical methodology seem to meet the needs of lawyers, although there may be communication problems similar to those met in other consulting work. In one exceptional type of case, however, which includes the notorious case of the People v Collins, it is suggested that statisticians may not be in a position to provide sensible answers to the questions posed by the police and lawyers, and should be cautious about attempting to do so.