Juridical Proof and the Best Explanation
Michael S. Pardo
University of Alabama School of Law
Ronald J. Allen
Northwestern University Law School
Law and Philosophy, Forthcoming
U of Alabama Public Law Research Paper No. 1003421
Analytical and empirical studies of the process of legal proof have sought to explain the process through various aspects of probability theories. These probability-based explanations have neglected the extent to which explanatory considerations themselves explain juridical proof. Similar to many scientific inferences, juridical inferences turn on how well the evidence would explain certain conclusions. This inferential process, well known in the philosophy of science, is referred to as abduction or "inference to the best explanation." In this essay, we provide a detailed account of the process in general; an explanation-based account of juridical proof in particular; a comparison with probability approaches; and the theoretical and practical consequences of the debate.
We demonstrate how an explanation-based approach itself better explains juridical proof, at both the macro- and micro-levels, than the probability approaches. The macro-level issues include burdens of proof in civil and criminal cases, and related issues involving summary judgment, judgments as a matter of law, and sufficiency-of-the-evidence standards. The micro-level issues include the relevance and probative value (and thus the admissibility) of any individual item of evidence, from first-hand observations to complex scientific or statistical evidence. The explanatory considerations can provide practical guidance and constraint for decision-making on each of these issues. More generally, we demonstrate that the explanatory and probability approaches are not alternatives. The explanatory considerations are more fundamental, on which the probability accounts are parasitic. Thus to extent the probability approaches account accurately for and supplement explanatory considerations, they may improve our understanding; to the extent they do not, they risk mismodeling the process.
Number of Pages in PDF File: 47
Keywords: evidence, proof, abduction, inference to the best explanation, probability, burdens of proof, probative value
Date posted: July 29, 2007 ; Last revised: November 9, 2007