How do media contribute to the dissemination of conspiracy beliefs? A field study combining panel and web tracking at the outbreak of the COVID-19 pandemic

Abstract As COVID-19 escalated into a global health crisis, pandemic-related conspiracy theories emerged rapidly. Understanding how and under which conditions media influence their dissemination is essential. This study leverages unique data from 2-wave survey panels in Germany and German-speaking Switzerland, along with online tracking, to explore how individuals’ preexisting beliefs and media exposure influence the formation of pandemic-related conspiracy beliefs. The findings reveal direct exposure effects: alternative media, when supporting the conspiratorial claims, fostered conspiracy beliefs while mainstream media reduced conspiracy beliefs after debunking. Preexisting beliefs further conditioned these effects: individuals with strong populist views or low political trust selectively engaged with alternative media and selectively avoided mainstream sources. This resulted in two indirect pathways to the dissemination of conspiracy beliefs: people who selected into conspiracy-supporting content on alternative media experienced a reinforcement of conspiracy beliefs whereas people who (partially) avoided mainstream media counterargued the conspiracy-opposing information, also strengthening their conspiracy beliefs.