Partisanship: the true ally of fake news? A comparative analysis of the effect on belief and spread

Introduction: After the recomposition of the Portuguese parliament with the emergence of the radical right, this study explores the influence of partisan orientation on the belief and dissemination of fake news. Methodology: An exploratory sample was used (N = 712), whose participants were exposed to 20 politically biased headlines (pro-right and pro-left): half fake news and the other half true news. Participants evaluated their credibility and willingness to share them on social media. Results: Right-wing supporters are more likely to create and share compatible fake news. This trend was verified in all the measurement parameters of partisanship ((1) voting intention, (2) partisan sympathy and (3) self-placement on the I-D scale), in contrast to what was revealed with left- wing partisans. Discussion and conclusions: Only right-wing supporters show a tendency to believe more in fake news that favors their orientation. The same is not the case with left-wing individuals. However, both right-wing and left-wing supporters are more likely to share biased content. We believe that people with a right-wing party identity may be more exposed to disinformation in Portugal, as most disinformation sites seek this specific audience.