Adversary Voting in the Czech Chamber of Deputies (1993–2013)

Abstract The paper explores the legislative unity of government and opposition blocs in the Czech Chamber of Deputies over a period of 20 years. As voting unity is usually rather low in the Czech Republic, temporarily high concentrations of votes by these blocs are linked to higher rates of conflict between the government and opposition. I use the Rice and UNITY indices to compare average unity scores of individual cabinets and also explorative time series of unity vectors in order to analyse bloc concentration, success rate, and increased conflict. The outcomes are relevant both as comprising a case study and methodological observations: (1) Broad differences in the logic of interaction are confirmed (e.g. caretaker cabinets show less conflict than standard cabinets). Although no universal trend (e.g. no transition from consensual to conflictual practice) is found, the Czech opposition became more concentrated and resorted to serial blocking tactics in the second decade; thus, a major change of behavior occurred after all. (2) The Rice and UNITY indices correlate considerably; UNITY’s discrimination capacity is not distorted significantly despite the nature of equilibria in the Chamber. Moreover; the UNITY index is able to easily distinguish contested votes not detectable by the Rice index alone.