This paper investigates the interplay between pernicious polarization, autonomy of civil society - here called civil society capture, and liberal democracy in Central and Eastern Europe from 2006 to 2020. In the absence of prior time-series data on pernicious polarization and civil society capture, this study built and analysed a dataset of these variables across the region, testing six hypotheses. The findings confirm that both pernicious polarization and civil society capture exhibited an increase during the study period across most CEE countries, the findings also confirm hypotheses linking polarization/civil society capture with democracy, revealing a negative correlation between these variables and liberal democracy. Moreover, a qualitative analysis conducted on four countries highlighted mechanisms through which polarization might contribute to democratic decline. Factors such as the depth of polarization, divisive rhetoric, and sociocultural divides emerged as crucial elements in potentially fuelling democratic backsliding.