Author: Licia Claudia Papavero, Francesco Zucchini
Studies on female legislative behavior suggest that when introducing and/or approving a feminist agenda is at stake, women parliamentarians may challenge party cohesion by allying across party lines (Swers 2002; Sanbonmatsu 2006). However, evidence is mixed (see for example Lloren 2011), and how and why gender cohesion within the legislature may emerge and whether it is actually a threat to party cohesion are still open questions.
In this paper we analyze a specific parliamentary activity – bill co-sponsorship – in the Italian Parliament as a source of important information about MPs’ original preferences (see Aleman & alt. 2009) and we study how gender affects party cohesion. Do women form a separated group in the Italian parliament? On average, are they more or less distant from the center of their parties than men? Does gender affect systematically party cohesion?
The paper is innovative both for the data source and the methodological approach. We use a principal component analysis of co-sponsorship data gathered in the Italian lower chamber (Curini & Zucchini 2012) between 1983 and 2008 in order to indentify the ideal points of MPs in a multidimensional space for each legislature. The data obtained from this technique allow us to estimate the impact of gender on party cohesion at the individual level while controlling for the impact of several other variables of different kind (individual, partisan and institutional). We find that: 1) on average women show higher gender cohesion inside the parties and higher party cohesion than men; 2) gender’s effect is not conditional on individual characteristics, the size and organization of the parliamentary parties and the share of women members of the latter; 3) the different behavior of women MPs may depend on the different patterns of female recruitment in the parties.