Citizens do not directly observe democratic backsliding and, as a result, may hesitate to respond to subversion. We develop a model of third-party oversight bodies, such as the media or courts, that detect and assess actions that may be subversive to democracy and inform citizens. Oversight deters subversion, disciplines incumbents, and enables corrective actions by providing credible information about ambiguous incumbent behavior to citizens. However, when the oversight body is contested, citizens may doubt the intent behind its criticisms. When the oversight body is cautious in its criticisms, it elicits negative inferences about its intentions, what we term a fake news effect. The consequences are severe, undermining oversight and enabling backsliding. Democratic accountability depends on reliable sources of information and elected officials’ commitment to upholding norms of conduct.