Coalitions

A coalition is the temporary cooperation of different individuals, groups, or political parties to achieve a common purpose, which can be either short term or long term. Almost all politics can be conceived as involving the formation of some kind of coalition. Pressure groups, social movements, and political parties are coalitions of individuals with a common interest; governments can be formed by coalitions of political parties, not only in parliamentary regimes but also in regimes of division of powers; maintaining political stability or resolving political or ethnic conflicts can induce the formation of broad coalitions committed to support a new regime; and different governments and states can form military coalitions unified under a single command. A coalition implies cooperation among its members. A relationship of conflict usually develops between different coalitions whose members have opposite interests.

The most usual analyses of coalitions in politics deal with the formation of multiparty cabinets in parliamentary regimes. In government coalitions, several political parties cooperate, usually during a legislative term between two elections. Coalition governments are the most usual form in most parliamentary regimes using [Page 287]electoral rules of proportional representation, which typically do not produce a single-party majority of seats. This includes most countries in continental Europe, as well as other democratic countries such as India, Israel, and New Zealand. However, other broad coalitions have resulted from political settlements or conflict resolution, such as in South Africa, Zimbabwe, Kenya, or Madagascar, often involving international or external moderators.

An example of government formation in parliamentary regimes is Germany, where all cabinets since the end of World War II have been multiparty coalitions. The chancellor or prime minister has always been either a Christian Democrat or a Social Democrat, but government coalitions include several formulas: rightist Christian Democrats (always with their allies, the Bavarian Social Christians) with center-right Free Democrats, center-left Social Democrats with Free Democrats, Social Democrats with left Greens, and the so-called “grand coalition” of Christian Democrats and Social Democrats. All these governmental formulas have had majority support in terms of both popular votes and parliamentary seats. Due to the long-term participation of a few parties in government and other institutional mechanisms, the degree of stability in major public policies in Germany is very high. In contrast, the alternation of single-party cabinets when different parties receive a majority of seats in successive elections, as in Britain, may provoke periodic shifts in major public policy making.

Within political science, the formation and termination of cabinet coalitions have been analyzed as cooperative games in game theory. Both the search for office and the search for policy or ideological goals can be presumed to be realistic and legitimate motivations of politicians when they try to form a multiparty coalition. At the time of forming government, the interest of members of parliament in enjoying as much power as possible translates into the aspiration to accumulate as many government portfolios or ministries as possible for their party. This becomes a criterion to form a coalition with the minimum viable size. The explanation for this is that if a government is formed of a multiparty coalition without superfluous members, it can give each party a relatively high share of power to exert and enjoy. In a minimum winning coalition, each of its party members is pivotal, in the sense that the loss of a party would render the coalition no longer a winning coalition. In the particular case when a party has an absolute majority of seats in parliament, the minimum winning “coalition” is the majority single-party government without additional partners.

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