Duverger's law

Duverger's law

Duverger's Law is a principle which asserts that a first-past-the-post election system naturally leads to a two-party system. There are those who would argue this is not necessarily a negative outcome; however, some researchers and mathematicians have devoted considerable time developing alternative voting systems that do not appear to be subject to Duverger's Law.

The discovery of this principle is attributed to Maurice Duverger, a French sociologist who observed the effect in several papers published in the 1950s and 1960s. In the course of further research, other political scientists began calling the effect a “law.”

A frequent consequence of Duverger's law is the spoiler effect, where a third-party candidate takes votes away from one of the two leading candiates.

External links

Maurice Duverger, "Factors in a Two-Party and Multiparty System," in Party Politics and Pressure Groups (New York: Thomas Y. Crowell, 1972), pp. 23-32.

William H. Riker, The Two-party System and Duverger's Law: An Essay on the History of Political Science American Political Science Review, 76 (December, 1982), pp. 753-766. (This link is only accessible to individuals with access to JSTOR through a university, a corporation or another organization.)