Because of requirements that single-member districts be relatively equal in population, single-member districts often do not reflect distinct geographic communities as signified by municipal, county or other administrative boundary lines. This does not mean, however, that political representation has been divorced from the notion of 'community' in countries that delimit single-member districts.
Many countries that delimit single-member districts continue to emphasise the importance of creating districts that correspond as closely as possible to pre-existing communities, defined as administrative divisions and/or 'communities of interest.' The rationale for recognising communities in redistricting is that electoral districts should be more than conglomerations of arbitrary, random groups of individuals. Districts should, as much as possible, be cohesive units with common interests related to representation. This makes a representative's job of articulating the interests of his or her constituency much easier.
Defining Communities of Interest
A 'community of interest' is rarely defined by statute but it is generally thought of as a group of individuals united by shared interests or values. These shared interests may be the result of a common history or culture, a common ethnic background, or a variety of other ties that create a community of voters with distinct interests.
Although the perimeter of a community of interest may correspond to the boundaries of an administrative division, this is not necessarily the case. For example, a river may form a boundary between two administrative divisions, but the entire river valley may comprise a unified community of interest. In this instance, an electoral district that follows the administrative boundary would divide a community of interest.
In general, criteria related to communities of interest can be divided into three categories: (1) criteria related to administrative or geographic boundaries; (2) criteria related to common interests or common characteristics; and (3) criteria related to patterns of interaction. Criteria related to administrative or geographic boundaries are discussed under 'geographic criteria' (see Geographic criteria).
Some of the criteria related to common interests or characteristics are:
- Shared racial or ethnic background
- Common history and/or culture
- Common religion or language
- Shared socio-economic status
Some of the criteria related to patterns of interaction are:
- Transportation patterns
- Economic ties
- Communication networks (media markets)
Countries specifying that communities of interest be considered for redistricting have adopted a variety of approaches. Some countries regard communities of interest as the basic redistricting criterion, with all the other criteria subsumed below it as components of communities of interest. Other countries regard communities of interest more as a residual concept, filling holes left in a list of more specific redistricting criteria, such as the consideration of administrative boundaries and geographical features.
Despite the ambiguity inherent in the term 'communities of interest,' redistricters in many countries take communities of interest into account when drawing electoral boundaries. Redistricters knowledgeable about local conditions can sometimes identify communities of interest, but more often these communities are identified through a public hearing process.
Conclusion
Redistricting criteria inevitably conflict with one another. One possible means to resolve a conflict between criteria is to determine the most salient or most important 'community of interest' in a given instance. Public hearings are essential to this process. For example, a redistricting plan that follows ethnic community boundaries rather than administrative boundaries may prevail if members of the public assert that the ethnic community boundaries are more relevant to them than administrative boundaries.