Probability Discounting of Legal and Non-Legal Outcomes

Abstract

Probability discounting describes how the subjective value of an outcome changes because its delivery is uncertain. Although many legal decisions involve probability discounting, it has not been systematically studied. Participants were recruited to complete a probability-discounting task that assessed two legal (i.e., murder & embezzlement) and two non-legal (winning a sweepstakes & receiving medical treatment) hypothetical scenarios. They also completed several measures to assess attitudes related to legal issues. Different rates of discounting were observed across the four scenarios. Factor analysis indicated that discounting of the legal scenarios loaded onto a different factor than one of the non-legal scenarios (with the other cross loading on both). Only the participants' estimation of what constituted reasonable doubt was a reliable predictor of their rates of discounting of the legal outcomes. The present results have a number of potential social implications, both for the study of probability discounting and the understanding of legal decision-making. They also highlight the need for more experimental research on overt behavior.