Overview of treatment materials.

Misinformation has emerged as a major societal concern. But why do citizens contribute to the dissemination of falsehoods online? This article investigates this question by focusing on the role of motivated reasoning and, in particular, perceptions of group-based conflict. It examines the effect of perceived conflict on the endorsement of false news in the context of a regional conflict between Russia and the West as experienced by Ukrainian citizens. In our survey experiment, a sample of Ukrainians (N = 1,615) was randomly assigned to read negative false news stories about Russia, the European Union or Tanzania–a country with no stakes in the conflict. The results show that higher perceived conflict between Ukraine and Russia makes Ukrainians less likely to endorse false news targeting the European Union, but more likely to endorse false news that paint a negative picture of Russia. This finding extends the support for motivated reasoning theory beyond Western contexts investigated so far. Importantly, the effects of conflict perceptions remain strong after controlling for group identity and political knowledge of participants. These results advance our understanding of why false information is disseminated and point to the importance of conflict de-escalation to prevent the diffusion of falsehoods.