Liars, Damned Liars, and …

Abstract

The admission of expert opinion by courts meant to assist the trier of facts has enjoyed a checkered history within the Anglo-American legal system. Progress has been achieved where expert testimony proffered was determined by the court to be relevant, material, and competent. Cases where these criteria of admissibility remained undeveloped, or were misapplied in the face of complex evidence, expert testimony has done more harm than good in the search for truth. From Pascal and Fermat to se Moivre, from Bayes to Fisher, probability and data have come together to establish the role of statistics in civil and criminal justice. We explore the role statisticians as expert witnesses have played within the Anglo-American system of justice - in the US courts and in the Indian subcontinent. The evolution of the 1872 Indian Evidence Act has in many ways paralleled the changing rules of evidence and expert testimony in U.S. federal and state statutes. This is evident in the challenges courts in both places have faced, for example, in the application of the Daubert guidelines in cases involving complex, scientific data - in matters of DNA evidence, the environment, public health, etc. Lastly we look at the extent to which the two legal systems have retained the adversarial system as a check on expert opinion and its misuse.