Multi-party system

A multi-party system is a system in which multiple political parties have the capacity to gain control of government separately or in coalition. The effective number of parties in a multi-party system is normally larger than two but lower than ten. It is a system where there are large amounts of major and minor political parties that all hold a serious chance of receiving office, and because they all compete, a majority may not come to be, forcing the creation of a coalition.

Unlike a single-party system (or a non-partisan democracy), it encourages the general constituency to form multiple distinct, officially recognized groups, generally called political parties. Each party competes for votes from the enfranchised constituents (those allowed to vote). A multi-party system prevents the leadership of a single party from controlling a single legislative chamber without challenge.

If the government includes an elected Congress or Parliament the parties may share power according to proportional representation or the first-past-the-post system. In proportional representation, each party wins a number of seats proportional to the number of votes it receives. In first-past-the-post, the electorate is divided into a number of districts, each of which selects one person to fill one seat by a plurality of the vote. First-past-the-post is not conducive to a proliferation of parties, and naturally gravitates toward a two-party system, in which only two parties have a real chance of electing their candidates to office. This gravitation is known as Duverger's law. Proportional representation, on the other hand, does not have this tendency, and allows multiple major parties to arise.

A two-party system requires voters to align themselves in large blocs, sometimes so large that they cannot agree on any overarching principles. Along this line of thought, some theories argue that this allows centrists to gain control. On the other hand, if there are multiple major parties, each with less than a majority of the vote, the parties are strongly motivated to work together to form working governments. This also promotes centrism, as well as promoting coalition-building skills while discouraging polarization.

Brazil, Canada, Denmark, Finland, France, Germany, India, Israel, Indonesia, Japan, Russia, Ireland, Mexico, the Netherlands, New Zealand, Taiwan and Sweden are examples of nations that have used a multi-party system effectively in their democracies (though in many cases there are two parties always larger than the others). In these countries, usually no single party has a parliamentary majority by itself. Instead, multiple political parties usually form coalitions for the purpose of developing power blocs for governing.

See also

• Coalition
• Polarized pluralism