ABSTRACT
This chapter posits that previous measurements of (legislative) party switching, conducted primarily for statistical purposes, have been oversimplified and focused solely on noting a parliamentarian’s change of (parliamentary) party affiliation without considering its context. However, examples from Central and Eastern Europe demonstrate that not all events of parliamentary group affiliation changes are simple to qualify. For this reason, all non-standard trajectories of parliamentary mandate exercise resulting in the attribution of a given event to the category of legislative party switching are considered. Clear recommendations for future analyses are formulated and supported by specific examples. These recommendations pertain to how to count legislative party switching in the case of covert pre-election or parliamentary coalitions, splits and mergers of parliamentary groups, party rebranding, and MP’s replacement. Consideration will also be given to the technical timing of membership of non-affiliated parliamentarians, which should not imply the recording of legislative party switching, and the problem of so-called ‘one-day’ parliamentarians who do not hold a de facto mandate, although they are recorded de jure. The chapter justifies the adoption, in the research, of the perspective of counting legislative party switching, taking into account political pragmatics, and not only formal aspects.
