Verba Volant, Scripta Manent? Party Conferences and Intra-Party Cohesion in Italy and France

Parties’ ability to maintain parliamentary discipline and an image of internal cohesion determine important outcomes such as government formation, policy change and even future electoral success. Consequently, researchers paid attention to intra-party cohesion. They historically evaluated the level of intra-party cohesion based on roll call votes or parliamentary speeches. Several scholars, however, suggest developing alternate measures of cohesion that are exogenous to legislative behavior. To this end, recent studies have started to investigate debates at party conferences as a source of data on party cohesion. Some studies focused on oral speeches delivered by politicians during these intra-party debates, while others paid attention to the content of written motions presented by party factions. To what extent these two sources tell the same picture? We answer this question estimating intra-party polarization through automated text analysis techniques. For this purpose, we analyze approximately 50 congresses of Italian parties and 15 congresses of French parties held between 1990 and 2015. We separately analyze speeches and motions, comparing the estimates produced by these two data-sources to assess similarities and differences. Furthermore, we try to identify which elements could explain divergent levels of cohesion. In this regard, we expect systematic differences according to features such as intra-party rules, party size, cabinet membership or the timing of elections. The results assess the role of party congresses as suitable sources of data on intra-party dynamics, shedding light on potential selection bias in observing contested party congresses and allowing us to evaluate to what extent intra-party debates are subjected to party discipline.