Legal Threats and Online Dissent: Evidence from Social Media Regulation in Turkey

We study how legal threats to social media platforms shape online political communication. We exploit the sharp implementation of a 2020 Turkish law that required social media companies to establish local offices and provide user data to the government on request. Assembling a panel of over 700 Twitter users and 7 million posts, we use a differences-in-differences design to compare dissenters, individuals publicly critical of the reform when announced, to other groups unlikely to be affected, such as celebrities. We find that dissenters and political exiles post 15-20 percent fewer tweets following implementation, and engagement with their content falls sharply. These short-run chilling effects emerge despite limited platform compliance, indicating that anticipated enforcement risk, rather than actual enforcement, drives the effect. In the long run, the chilling effects dissipate. Our findings suggest that states can govern online speech indirectly, by regulating platforms rather than users, but that such effects may be self-limiting in the absence of visible enforcement.