A Probabilistic Analysis of the Sacco and Vanzetti Evidence

Book excerpt: A Probabilistic Analysis of the Sacco and Vanzetti Evidence is aBayesian analysis of the trial and post-trial evidence in the Saccoand Vanzetti case, based on subjectively determined probabilitiesand assumed relationships among evidential events. It applies theideas of charting evidence and probabilistic assessment to thiscase, which is perhaps the ranking cause celebre in all of Americanlegal history. Modern computation methods applied to inferencenetworks are used to show how the inferential force of evidence ina complicated case can be graded. The authors employ probabilisticassessment to obtain opinions about how influential each group ofevidential items is in reaching a conclusion about the defendants'innocence or guilt. A Probabilistic Analysis of the Sacco and Vanzetti Evidence holdsparticular interest for statisticians and probabilists in academiaand legal consulting, as well as for the legal community,historians, and behavioral scientists. It combines structural andprobabilistic ideas in the analysis of masses of evidence fromevery recognized logical species of evidence. Twenty-eight chartsshow the chains of reasoning in defense of the relevance ofevidentiary matters and a listing of trial witnesses who providedthe evidence. References include nearly 300 items drawn from thefields of probability theory, history, law, artificialintelligence, psychology, literature, and other areas.