Information Transmission in Debate

The paper considers the informational role of legislative debate, modeled as cheap-talk. In such circumstances, can debate affect legislative decisions? Through a series of examples, based on an endogenous agenda-setting model of legislative decision making, I argue (I) that debate can only affect outcomes when the legislators' underlying preferences are not too dissimilar (cf. Crawford and Sobel 1982) and (2) that the only informational role of debate for legislative decisions is one of timing; that is, the information commonly available at the final stage of decision making (voting) when there is no debate is identical to that commonly available with debate. So debate does not elicit information that otherwise would not be made available during the decision-making process. Instead, it allows individuals to share their private data in time for them to be used in agenda setting rather than only in voting.