Vanderbilt Law Review

First Page



Nearly all interesting legal issues require accurate predictions about human behavior to be resolved satisfactorily. Judges, policy- makers, and academics invoke mental models of individual and social behavior whenever they estimate the desirability of alternative rules, policies, or procedures. Contemporary legal scholarship has come to recognize that if these predictions are naive and intuitive, without any strong empirical grounding, they are susceptible to error and ideological bias. Something more rigorous is thus expected when normative claims are advanced, and the place of the social sciences has expanded in legal discourse to satisfy this expectation.'

Three branches of the social sciences-economics, psychology, and sociology-offer the most obvious assistance in predicting everyday human behavior, and each has a well-recognized history of influence on legal scholarship. The legal realists-most notably, Jerome Frank--took psychology quite seriously half a century ago; "sociological jurisprudence" came to prominence shortly thereafter, and law and society studies are still highly visible. But as many have said so often, both psychology and sociology have suffered from the inability to generate a unified behavioral model rivaling the simplicity, elegance, and testability of the economist's utility- maximizing rational actor. For this reason (and probably a host of others), the rational actor model came to dominate predictions about how "normal" persons and groups respond to legal incentives. By the late 1970s and early 1980s, law and economics was the one social science-based approach to have a truly pervasive effect on legal thinking. "Law and psychology" for some time was largely the study of either marginal segments of the population, such as the criminally insane, or specialized procedural subjects like jury behavior and eyewitness recall.