A constituency is any cohesive corporate unit or body bound by shared structures, goals or loyalty. It can be used to describe a business's customer base and shareholders, or a charity's donors or those it serves. The most common meaning of constituency occurs in politics and means the group of people or geographical area that a particular elected representative or group of elected representatives represents. The rest of this article deals with this sense of constituency.
Specifically, a constituency often refers to the group or area from which voters in an election are drawn. Depending on the electoral system being used, a constituency may elect one or more members. For instance, in the United Kingdom, Westminster Parliamentary constituencies each elect one Member of Parliament using a first past the post system (though some used to elect more than one), while the larger European Parliamentary constituencies each elect a number of Member of the European Parliament (see 'Regions of England').
A marginal constituency is one where the margin between the expected voting for the major parties in an election is slim. In United Kingdom general elections, the voting in a relatively small number of marginal constituencies usually determines the outcome of the entire election.
Republic of Ireland
Constituencies in the Republic of Ireland elect between three and five TDs, while constituencies between 1536 and 1800 in the Kingdom of Ireland used to return two MPs.
In the United Kingdom, a parliamentary constituency is sometimes called a Parliamentary seat or a Division. Constituencies for local government elections are called Wards.
As of 2005 there are 646 constituencies in the UK:
Northern Ireland constituencies elect six MLAs to the Northern Ireland Assembly.
The Scottish Parliament has 73 single-member constituencies elected on a First Past the Post basis, with eight Scottish regions acting as European parliament constituencies.
The National Assembly for Wales has 40 constituencies similarly elected.
In the United States, electoral constituencies for the federal House of Representatives are known as congressional districts, while the constituencies for the variously named state legislatures go by a variety of names. Long standing practice, reinforced and modified by several U.S. Supreme Court decisions, require the equalization of populations of constituencies after each decennial census, a process known as redistricting. When driven by partisan bodies, this process opens up the possibility of gerrymandering for political or factional advantage. A Pennsylvania legislator long active in redistricting issues, State Rep. Mark B. Cohen of Philadelphia, said that "In election years, constituents choose their legislative officials. In redistricting years, legislative officials usually try to choose their future constituents."
In Germany there are 299 electoral constituencies (called Wahlkreise) for the Bundestag (Germany). In those elections where representatives are elected by the "First Past the Post electoral system" (for example the European Parliament, Bundestag, and federal state parliament) these same constituencies also serve.
The constituencies are divided so that each has approximately the same number of voters. German electoral law dictates that the deviation from average of all constituencies shall not exceed a certain figure (see for example § 3 Abs. 1 Nr. 3 in German electoral law). Other restrictions prevent abuses such as gerrymandering.
In Canada, they are legally known as electoral districts (fr: circonscriptions) for Members of Parliament and Members of Legislative Assemblies at the provincial level, although "constituency" and the informal term "riding" is also used. In Australia, federal and state constituencies are known as electorates or seats .
In Switzerland the Canton of St. Gallen uses the Wahlkreise (Constituency or electoral district) in place of the previous, and more usual, district. See Canton of St. Gallen#Constituencies and municipalities.
Places with constituencies
In France, electoral constituencies are known as circonscriptions électorales. Most of the British Commonwealth uses constituencies as electoral divisions. For details of constituencies in these and other places see:
Marginal constituencies are also known as: