Determinants of Parliamentary Turnover in Western Europe 1945-2015

The renewal and stability of the political elite has attracted the interest of scholars and the public alike since antiquity. Parliamentary turnover, which is a specific type of political elite circulation that refers to the level of membership change in legislatures after general elections, is associated with the rise of modern representative democracy in the 1800s. Its study is important because the rate of political alternation in parliaments is a measure of the volatility of the governing elite (elite seismometer); an index of the competitiveness of representative democracy and especially of the stability of the political order and of the level of descriptive representation (democratic thermometer); and finally a measure of the existence of the necessary conditions for policy change (a policy barometer). 

Although the topic has attracted the attention of scholars since the start of the 20th century, past research is still characterised by major empirical gaps and interesting puzzles. Such a significant empirical lacuna concerns systematic research outside the US context. The major paradox relates to the contradiction between analytical findings according to which turnover is primarily a matter of electoral swings and the matching effects of electoral systems with the observation according to which the majority of MPs turn over before elections.

The dissertation attempts to solve this puzzle by addressing three specific empirical questions, which also present key empirical gaps in the literature. 

1. What explains legislative turnover in lower chambers within West European consolidated democracies in the period 1945-2015?

2. Do explanations of the political alternation of women MPs in West European legislatures differ than those of men? And what can we learn about the determinants of legislative turnover through the study of its gender dimension? 

3. How much personnel change is there  within and across legislative parties across time and why?

The questions are answered with the help of an original dataset (Parl-Turn), which comprises 18151 individual level observations on new members of parliament (MPs), 1359 observations on legislative turnover within political parties and 152 observations on turnover at the entire assembly level in the lower or unicameral chambers of Austria, Belgium, France, Italy, the Netherlands, Sweden, Switzerland and the UK over a period of 70 years (1945-2015).

The key finding emerging from the results is that membership change in parliaments from election to election is primarily a supply side phenomenon. The structure of political career opportunities, or simply put the attractiveness, availability and accessibility of political jobs in the political marketplace, shapes the supply of contenders and thus affects the rate of political alternation in parliaments. The demand for candidates by parties and for legislators by electorates follows in importance. Electoral systems, although statistically significant are the least important. The finding signifies a departure from results of past internationally comparative studies according to which turnover is primarily a result of fluctuations in voter preferences (mainly electoral volatility) and differences in the electoral system.