Delimitation of constituencies

Boundary delimitation (or simply delimitation) is the drawing of boundaries, particularly of electoral precincts, states, counties or other municipalities. In the context of elections, it can be called redistribution and is used to prevent unbalance of population across districts. Unbalanced or discriminatory delimitation is called "gerrymandering." Though there are no internationally agreed processes that guarantee fair delimitation, several organizations, such as the Commonwealth Secretariat, the European Union and the International Foundation for Electoral Systems have proposed guidelines for effective delimitation.

In international law, the related national delimitation is the process of legally establishing the outer limits ("borders") of a state within which full territorial or functional sovereignty is exercised. Occasionally this is used when referring to the maritime boundaries as well, in this case called maritime delimitation.

Countries delimit electoral districts in different ways. Sometimes these are drawn based on traditional boundaries, sometimes based on the physical characteristics of the region and, often, the lines are drawn based on the social, political and cultural contexts of the area. This may need to be done in any form of electoral system even though it is primarily done for plurality or majority electoral system.

These processes of boundary delimitation can have a variety of legal justifications. Often, because of the powerful effects this process can have on constituencies, the legal framework for delimitation is specified in the constitution of a country. The Institute for Democracy and Electoral Assistance (IDEA) recommends the following pieces of information be included in this legal framework:

Delimitation is regularly used in the United States and Commonwealth countries. This is called redistricting or redistribution respectively. In these countries non-partisan commissions draw new districts based on the distribution of population according to a census.

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