Is Twitter biased against conservatives?

Social media companies are often accused of anti-conservative bias, particularly in terms of which users they suspend. Here, we evaluate this possibility empirically. We begin with a survey of 4,900 Americans, which showed strong bipartisan support for social media companies taking actions against online misinformation. We then investigated potential political bias in suspension patterns and identified a set of 9,000 politically engaged Twitter users, half Democratic and half Republican, in October 2020, and followed them through the six months after the U.S. 2020 election. During that period, while only 7.7% of the Democratic users were suspended, 35.6% of the Republican users were suspended. The Republican users, however, shared substantially more news from misinformation sites – as judged by either fact-checkers or politically balanced crowds – than the Democratic users. Critically, we found that users’ misinformation sharing was as predictive of suspension as was their political orientation. Thus, the observation that Republicans were more likely to be suspended than Democrats provides no support for the claim that Twitter showed political bias in its suspension practices. Instead, the observed asymmetry could be explained entirely by the tendency of Republicans to share more misinformation. While support for action against misinformation is bipartisan, the sharing of misinformation – at least at this historical moment – is heavily asymmetric across parties. As a result, our study shows that it is inappropriate to make inferences about political bias from asymmetries in suspension rates.