The way in which district or constituency boundaries are drawn can be of as crucial importance to the final results as the type of electoral system used. That is why an entire section of this site has been dedicated to assessing the science of districting, see Electoral Systems that Delimit Electoral Districts.
At one extreme, single member district boundaries can be 'gerrymandered' to the advantage of one particular party or group. This was particularly apparent in the Kenyan elections of 1993 when huge disparities between the sizes of electoral districts - the largest had 23 times the number of voters as the smallest - contributed to the ruling Kenyan African National Union party's winning a large parliamentary majority with only 30% of the popular vote. However, gerrymandering is also common in local government in the United States where the party controlling the state legislature often has control over districting.
Boundary designers often work to three major principles when drawing lines around people on a map:
- Compactness - the district should be reasonably compact when it comes to geography and the distribution of voters.
- Cohesive - attention is paid to communities of interest and geographical terrain.
- Contiguous - the district should be in one unbroken inter-connected piece.
It is true to say that boundary delimitation becomes a much greater problem and important issue the smaller the number of members elected from the district. Boundary delimitation for single member districts is the most politicized science.
