Here are two common ways of thinking about democracy in the online era. First, the internet is a liberation technology and will usher in an era of global democracy. Second, you can have social media or democracy, but not both.

Which is more correct? There is no doubt democracy is in retreat around the globe. Even supposedly stable democracies have recently seen events incompatible with democracy and the rule of law, such as the violent assault on the US Capitol in 2021.

To understand the role of social media in this process, we carried out a systematic review of the evidence linking social media to ten indicators of democratic well-being: political participation, knowledge, trust, news exposure, political expression, hate, polarization, populism, network structure, and misinformation. Our findings are published in Nature Human Behaviour.

We reviewed almost 500 studies across different platforms in countries around the globe, and saw some broad patterns emerge. Social media use is linked to an increase in political engagement, but also increases in polarization, populism, and distrust in institutions.