Inter-factional conflicts and government formation: Do party leaders sort out ideological heterogeneity?

Although a large branch of the literature takes parties as monolithic actors, we know that they are teams composed by a variety of subgroups. Hence we consider the party as a coalition of factions that must overcome collective action problems. On the one hand, factions compete to maximize their share of payoffs, while on the other they need to cooperate preserving unity, which is a public good. To deal with this conflict the party select a leader who is in charge of organizing the subgroups in order to produce the public good. Due to problems in ensuring credible commitment, inter-factional conflict and ideological heterogeneity may affect coalition formation jeopardizing party?s chances of getting into government. We estimate the ideological heterogeneity of Italian parties, from 1946 to 2010, using a new dataset, built through quantitative text analysis of policy documents presented by factions during party congresses.
These data have been used to assess whether and to what extent internal polarization damages the party?s likelihood of being involved in the ruling coalition. The impact of inter-factional conflict has been investigated in interaction with intraparty rules. In fact, contrasting modes of party organization may alter the degree of autonomy of the leader and its ability to solve factional disputes related to intra-party portfolio allocation or to the governments? policy platform. In this perspective, when the party leader is autonomous or he/she can rely on powerful whipping resources to impose discipline, the party will credibly sticks to the coalition agreement, thereby reducing the negative effect of factional heterogeneity in coalition bargaining.