This paper articulates a general distinction between two important communicative ideals—expressive sincerity and discursive integrity—and then uses it to analyze problems with political debate in contemporary democracies. In the context of philosophical discussions of different forms of trustworthiness and debates about deliberative democracy, self-knowledge, and moral testimony, the paper develops three arguments for the conclusion that, although expressive sincerity is valuable, we should not ignore discursive integrity in thinking about how to address problems with contemporary political debate. The paper concludes (...) with a brief discussion of a strategy for improving discursive integrity within public political debate by reflecting on which principles of responsible public debate would promote better democratic decision making. (shrink)