The Condorcet Jury Theorem and the Expressive Function of Law: A Theory of Informative Law

Abstract

Legal theorists often claim that law can influence behavior expressively, by the message that it embodies, rather than through enforcement of the sanctions that it imposes. This paper identifies and analyzes one possible mechanism by which legislation can generate compliance, even in the absence of a deterrent effect. Under certain circumstances, legislation may reflect the legislature's superior aggregation of information; this can cause individuals to update their beliefs about underlying features of the world, and thereby change their behavior. The main example used in the paper is a ban on public smoking, which may cause individuals to update their beliefs about the health dangers of second-hand smoke. Even if the legislature has no special expertise on such an issue, the Condorcet Jury Theorem implies that, given certain assumptions, legislation may aggregate information in a way that provides information superior to that held by any individual citizen. The paper introduces this idea using a basic model in which legislators receive a private signal about the issue and vote sincerely. Then, the complications posed by strategic voting, coordination, position-taking preferences, interest group lobbying, and institutional features of legislative organization are analyzed. We conclude that there exists significant scope for legislation to influence behavior and behavioral norms by conveying information from legislatures to citizens.