Technology can be a very effective tool for conducting electoral boundary delimitation, or redistributions of electoral boundaries. Powerful mapping technologies in particular, such as geographical information systems (GISs), as well as database software, can be used by election management bodies (EMBs) to assist with the boundary delimitation process.
The electoral boundary delimitation process can essentially be divided into two categories: determination of political boundaries (such as boundaries of parliamentary districts) and determination of administrative boundaries (such as boundaries of polling divisions).
Determination of political boundaries
Where political boundaries are being determined, there is often an element of "one vote-one value" included in the criteria for boundary distribution, as well as other more subjective criteria such as community of interests, means of communication and physical area. "One vote-one value" criteria generally require EMBs to ensure that either the number of people or number of enrolled electors residing in each district is within a specified range.
The process of drawing electoral boundaries that contain specified numbers of people or electors can be very complex, particularly where the permissible variation from the ideal quota is limited. The process can be complicated still further by requiring projected population growth to be taken into account. For example, for the Australian House of Representatives, a distribution of boundaries for the 51 districts in the State of New South Wales involves ensuring that the number of enrolled electors in each district is within 10% of the quota (or average number of electors in each district) at the time of the distribution, and that the number of enrolled electors estimated to reside in each district in 3 ½ years time is within 5% of the quota.
Technology can be used for this process by keeping track of the number of people residing in each parcel of land, and to allocate numbers of people to proposed districts which are made up of aggregates of parcels of land. "Point and click" boundary delimitation systems can allow EMB users to draw boundaries on computerised maps, which will then automatically calculate the numbers of people contained in each proposed district. This facility saves a great deal of manual calculation compared to "pencil and paper" systems of the past, thereby allowing EMBs to explore many more options than was feasible previously.
Technology can also be used to calculate population projections where distributions are required to take account of population growth rates.
Determination of administrative boundaries
Administrative boundaries are generally boundaries that are not linked directly to political representation on a "one vote-one value" basis. They can include boundaries of polling divisions, which are subdivisions of parliamentary districts that determine where individuals may vote. They can also include local government boundaries that are based on geographical or locality boundaries, rather than boundaries determined by numbers of residents, such as city councils.
Administrative boundaries do not tend to have strict criteria requiring specified numbers of people to be resident in each district. While there is less emphasis placed on determining numbers of residents in each district than there is with political redistricting, technology can still be used for the drawing of boundaries and with printing maps and other related output.
Passive and non-passive systems
It is possible to program boundary delimitation software to automatically draw boundaries according to the applicable criteria. This "passive" method takes the decision-making process away from people and relies on the instructions programmed into the software to produce a reasonable result. While the sophistication of GIS software continues to increase, computerised "passive" distributions are unlikely to produce boundaries that would be free from criticism, except in cases where the position of boundaries is of little importance.
Non-passive software allows the user to specify boundaries, and the software performs the necessary calculations to determine whether the criteria have been met. This method is most widely used as it allows users to draw logical boundaries using their knowledge of the process.
Passive systems can be combined with non-passive systems to provide a computer-generated starting point for users to manipulate as they see fit.
Applications of technology
Some examples of technology used for boundary delimitation purposes include:
obtaining relevant data, such as demographic, political and geographic data
defining and manipulating census tracts, or defined geographical areas used for census purposes
producing maps
publishing results of boundary delimitation and results of elections following boundary changes
using GIS to draw district boundaries
using GIS to evaluate redistricting plans