After its landslide victories of 2010, 2014 and 2018, Fidesz has introduced numerous institutional changes in the Hungarian political system. The academic research has emphasized the illiberal and antidemocratic character of these reforms, and the populist ideology of the party has been widely considered as the underlying force behind them. This study analyzes the most important reform that Fidesz has undertaken: the new Fundamental Law, enacted in 2012. We examine whether this change can be regarded as a violation of liberal democratic principles, and, if that is the case, whether it can be linked to the populist character of Fidesz. We found that some of the most criticized dispositions of the newly enacted constitution cannot be regarded as violations of liberal democratic principles, whereas other changes clearly constitute attacks to the foundations of Hungarian democracy, mainly affecting the separation of powers and the civil rights of minorities, These findings are largely consistent with the effects of populist governments on democracy as documented in the literature.