Research on the normative ideal of democracy has taken a sharp deliberative and epistemic turn. It is now increasingly common for claims about the putative cognitive benefits of political deliberation to play central roles in normative arguments for democracy. In this paper, I argue that the most prominent epistemic defences of deliberative democracy fail. Relying on empirical findings on the workings of implicit bias, I show that they overstate the epistemic virtues of political deliberation. I also argue that findings in cognitive and social psychology can aid in the development of a new and improved generation of epistemic arguments for deliberative democracy.