When should the criminal law intervene to deter and punish the promulgation of falsehoods that are intended to influence political – electoral or referendum ‐ campaigns? I will scrutinise the protection that UK criminal law provides for the interests of candidates, referendum campaigners and voters, from the (potential) effects of damaging falsehoods. I suggest that neither the protection of candidates’ or campaigners’ reputations, nor the promotion of the public good of collective decision‐making by voters based on accurate and adequate information, in themselves provide sufficient reasons for criminal law intervention. Falsehoods must normally be intended to threaten, undermine or prevent effective participation in the political process before the intervention of the criminal law is justified.