Constitutional Regulation of Freedom of Expression and Platform ‘Terms and Conditions’ in Digital Public Spheres

In the digital era, platforms serve as public forums. Nevertheless, the specific criteria for the removal of users' posts or the blocking of accounts are delineated in the platform's terms of service, which constitute private contracts. This has led to instances where freedom of expression is inadequately safeguarded in digital public forums. Given the contemporary challenges to freedom of expression in digital public spheres, it is imperative to systematically investigate the constitutional implications of platforms' infringement on the right to freedom of expression when they delete posts or block accounts, as well as the legal foundation for such actions as specified in their terms of service. Unlike the state, which is directly bound by fundamental rights, platforms are entities that can themselves enjoy these rights. The act of deleting users' posts is encompassed within the freedom of business operations; however, this action precipitates a conflict between users' freedom of expression and the platform's freedom of business operations. The principle of the substitutability of fundamental rights offers a potential resolution to such conflicts. Since the 2010s, the German Federal Constitutional Court has broadened the scope of fundamental rights by elucidating that private entities can also be subject to these rights. In alignment with this development, the German Federal Court of Justice recently determined that Facebook's terms of service, which permitted the deletion of hate speech posts and the blocking of users' accounts, were invalid based on the Art. 307 of German Civil Law. While terms of service are private agreements, they form the foundation for content moderation activities, such as the removal of posts or the suspension of user accounts. In this context, the interaction between the platform and the user evolves from a simple contractual relationship to a constitutional one, involving the limitation of freedom of expression. The deletion of posts or the blocking of accounts can only be justified when both substantive requirements—objectively verifiable criteria—and procedural requirements—such as notification and the opportunity to contest—are fulfilled, thereby ensuring the protection of freedom of expression on digital public platforms. Moreover, to enhance the safeguarding of freedom of expression on these platforms, it is imperative to consider legislative measures that mandate platforms to draft their terms of service with due consideration for fundamental rights.