Abstract
The party system in the Czech Republic was long considered as one of the most stable ones among CEE post-communist countries. The reason for this was especially low electoral volatility together with a steady number of political parties.
Nevertheless, since 2010 electoral volatility and the party system's fragmentation have risen considerably. Thus, the system is often described as destabilized and moving back to the early 1990s.
This paper utilizes data on MPs' votes on roll calls in the Czech Chamber of Deputies. I propose a unique dynamic item response theory model in order to depict the parties' spatial ideological positions and their moves during the last 25 years.
A specific selection of particular roll calls assures that the very left-right ideological spectrum is truly delineated. The analysis suggests that the party system does not move back but rather transforms into a new form of a moderate pluralism.
The spatial patterns of the parties' ideal points today are substantially different from those observable in the early 1990s. The most important finding is that for the first time in the modern history, two main opposing parties leading the polls cannot be differentiated along the left-right continuum.
Thus, to distinguish their political positions the parties need to rely more on scandals, campaigns, and personal charisma of party leaders. To summarize, the paper elucidates the transformation of the party system in the CEE country.
Consequently, the knowledge of these internal political factors can help to understand the country's external behaviour towards the European Union.