Lying in Persuasion

Abstract

We develop a model where the speaker strategically obtains information about which they can lie to persuade the audience. In the equilibrium where the option to lie is exercised, the speaker obtains more persuasive information than in the equilibrium where they speak the truth. The conditions for equilibrium with lying are restrictive: the risk that the speaker’s lie will be detected must be neither too small nor too large, and the audience must be sufficiently inclined ex-ante to do what the speaker is asking – lying is used to nudge, not to push. We apply the model to analyze persuasion by media and show how making fact-checking more prevalent may increase misinformation.