Can Biased State Media Change Minds? Null Evidence from Poland

We investigate the impact of exposure to biased media content on political attitudes, focusing on a specific government-controlled broadcaster in Poland. In an experiment (N = 1,943), we randomly assigned participants to either a treatment condition, where they read excerpts from a representative sample of articles published by this media outlet on divisive political topics, or to a control condition. We do not find evidence that exposure to these excerpts influenced political attitudes (such as distrust in the opposition, perceptions of outsider threat, and meta-perceptions of these attitudes in society). Additionally, there was no evidence that mentioning the source of the information affected the persuasiveness of the news articles, nor that party preferences or political interest moderates any of these effects. These findings raise questions about the causal role of biased media in political polarization during periods of high political discord.