Grand Coalition

Party alliances can be said to be grand coalitions when they involve at least two of the largest parties in parliament. Modern examples of grand coalitions include those between Austria's People's Party and Social Democratic Party (1945–1966, 1986–2000, and 2006-), and in the United Kingdom between Liberals and Conservatives (1916–1918). Grand coalitions should not occur under normal conditions. In standard coalition theory, parties will want to maximize their power in government. In William Riker's power-seeking model, parties will try maximize the number of portfolios they control within a cabinet. This implies that parties will want to form minimal winning coalitions, that is, they will want to form coalitions of the smallest size possible that will command a majority in the parliament. In rival models where parties are policy seeking, parties will want to form coalition governments with parties that are closest to them in ideological terms. Under either of the two major coalition theories, grand coalitions should not form. First, grand coalitions are, by their very nature, larger than minimal-winning. Second the larger the grand coalition, the broader the ideological spread of the parties within the government is likely to be.

There are circumstances where parties might find it in their interest to form grand coalitions. First, a centrist party might see advantages to having a grand coalition with parties both to the left and to the right, ideologically speaking, so that it can trade one off against the other. More particularly, however, grand coalitions occur when a nation is facing a major crisis. Major crises such as war or massive economic problems can lead big parties to set aside their ideological differences and unite against a common external threat. Sometimes smaller parties will be too fragmented to form stable alliance partners or to enable a parliamentary majority. Furthermore, an alliance between major parties can act as an effort to exclude extremist or anti-system parties from influencing legislative business. Because of the inherent size of grand coalitions, they have the potential to dominate legislative activity. This has been the case historically in the European Parliament with the coalition between the European People's Party (Christian Democrat) and the Party of European Socialists (Social Democrat). This example raises questions about the lack of institutional constraints on oligarchic coalition formation, and, given its emergence and longevity, questions the extent to which coalition behavior is really constrained by ideological considerations.