The spread of disinformation, such as false and fabricated content as amplified by the expansion of artificial intelligence systems, has captured the attention of policymakers on a global scale. However, addressing disinformation leads constitutional democracies to address questions, particularly regarding freedom of expression as the living core of a democratic society. If, on the one hand, this constitutional right has been considered a barrier to public authorities’ interferences, on the other hand, the spread of fabricated content and manipulative techniques, including deepfakes, challenge liberal views and move the constitutional perspective towards a reactive dimension. This constitutional question is further enriched by the role of online platforms which are essential tiles of a mosaic picturing the potential regulatory strategies and the limit of public enforcement to tackle disinformation. Between liberal and illiberal approaches to address online disinformation, the Union is advancing an alternative policy solution based on a regulatory mix, as underlined by the Digital Services Act, the Strengthened Code of Practice on Disinformation, and the Artificial Intelligence Act. Within this framework, this work argues that the European approach to disinformation is leading to a unique regulatory system focused on the dynamics characterizing the spread of online disinformation.