Because delimitation, or redistricting, practices vary greatly around the world, there are few universal principles to guide the delimitation process. Countries disagree on fundamental issues, such as how impartial and independent the process can and should be from the legislative and political concerns. But there are three generally accepted principles:
- 'representativeness';
- equality of voting strength;
- reciprocity.
Representativeness
Electoral district boundaries should be drawn such that constituents have an opportunity to elect candidates they feel truly represent them. This usually means that district boundaries should coincide with communities of interest as much as possible. Communities of interest can be defined in a variety of ways. For example, they can be administrative divisions, ethnic or racial neighbourhoods, or natural communities delineated by physical boundaries (such as islands). If districts are not composed of communities of interest, however defined, it may be difficult for a single candidate to represent the entire constituency.
Regardless of a representative's characteristics or political beliefs, however, a representative who performs constituency services and works to protect constituency interests in the legislature may be rewarded with re-election if the constituency views this as effective representation.
Equality of Voting Strength
Electoral district boundaries should be drawn so that districts are relatively equal in population. Equally populous districts allow voters to have an equally weighted vote in the election of representatives. If, for example, a representative is elected from a district that has twice as many voters as another district, voters in the larger district will have half the influence of voters in the smaller district. Electoral districts that vary greatly in population--a condition referred to as 'malapportionment'--violate a central tenet of democracy, namely, that all voters should be able to cast a vote of equal weight.
Reciprocity
The procedure for delimiting electoral districts should be clearly spelled out in legislation so that the rules regulating the process are the same, regardless of who is drawing the district boundaries. If the redistricting process is to be non-partisan, then all political parties must refrain from attempting to influence the outcome. If political concerns are permitted to play a role in the process, then all political parties must be given access to the process. If the legislature is to draw electoral district boundaries, then any political party that garners a majority in the legislature will have an opportunity to control the process. These rules must be clearly understood and must be acceptable to all major political parties and participants in the redistricting process.
