The Use of Evidence in Presidential Debates: A Study of Evidence Levels and Types from 1960 to 1988

Abstract

When preparing for presidential debate, candidates spend substantial time learning facts from briefing books. The present study examines whether or not this factual support actually improves a candidate's perceived effectiveness in a debate. Through content analysis, this study finds that higher rates of factual evidence are associated with “losing” a debate. Based on qualitative debate analysis, we argue that this association arises from three common mistakes candidates make when using evidence. To avoid these mistakes, we also offer Kennedy's argumentation method as a model for political success.