ABSTRACT
This chapter presents and discusses the results of analyses of the level of parliamentary volatility in the lower chambers of the Czech, Lithuanian, and Polish parliaments. The following measures were used in the research procedure: legislative party switching/switchers rates, index of parliamentary groups susceptibility to legislative party switching, and relative coefficient of legislative party switching intensity in a parliamentary group. The results confirm that the trend in legislative party switching intensity in Poland and the Czech Republic is decreasing, while in Lithuania, it is increasing. At the level of analysis of factions, it was found that opposition groups are slightly more resistant to volatility, and government-supporting groups are slightly less so, but pivot groups, balancing between government and opposition, remain the most vulnerable to the risk of leaving. With regard to the mainstream–populism axis, a clear predominance of vulnerability to volatility was found in populist groups. In the analysis of ideologically divided factions, no differences were observed between the right and the left, while it was clearly confirmed that extreme and non-ideological groupings were more prone to volatility, and moderate factions were much less so. No correlation was found between parliamentary volatility and the electoral system or electoral volatility.
