This thesis explores the status of liberal constitutional democracy in Lithuania and Latvia through the lens of democratic regression in Poland and Hungary, which has developed during the last decade. The primary focus of this thesis is Lithuania and Latvia. However, democratic backsliding in Poland and Hungary is used to frame the discussion around liberal constitutional democracy and how it can falter. This thesis will open with a critical literature review that details the distinct modes in which liberal constitutional democracy is eroded according to the prevailing theory in this area of research. Comparative case study methodology and doctrinal analysis are then used to determine the similarities between Hungary and Poland on the one hand and Lithuania and Latvia on the other. The body of this thesis will employ an inductive approach to facilitate a normative and empirical analysis of the nature of liberal constitutional democracy in Lithuania and Latvia. The benchmark of Poland and Hungary’s illiberal turn will be used to elucidate some of the common features of democratic deficit in the two member states under study and to understand whether Lithuania and Latvia are also at risk of authoritarian reversal. This comparative analysis shows that Lithuania and Latvia are also in the throes of their own democratic deficits. To explain these findings, this thesis distinguishes between democratic hollowness and democratic backsliding to differentiate the two concepts within the taxonomy of democratic ‘illnesses’. Hollowness is framed as a distinct feature of a low-quality democracy but one that can threaten democratic stability. This thesis also uses the agentic theory to illustrate the influence of political actors over the democratic trajectory of a country. Finally, the response of EU institutions to these threats is critically analysed before preventative measures are recommended to safeguard liberal constitutional democracy in Lithuania and Latvia.