Drawing electoral district boundaries is the second phase of the redistricting process. The drawing of federal electoral districts can either be done at the federal level or at the state or provincial level, once a specified number of districts have been assigned to the state or province. Drawing district lines proceeds in three stages:
- preparation of a redistricting database
- assignment of geographic units to districts, forming district boundaries
- production of a summary description and maps of the redistricting plan
Preparation of a Database
Before line drawing can commence, a redistricting database must be created. The database is composed of all of the geographic units that are to be used as the building blocks, and any population data, as well as any additional demographic and political data associated with these geographic units and deemed useful for redistricting. The geographic units may be as large as counties, cities or towns, or as small as voting areas or city blocks.
Formation of District Boundaries
After the database has been created, district boundaries can be formed. This involves adjusting the boundaries of existing districts and/or creating new districts. The process entails assigning, or reassigning, geographic units to districts until all units have been assigned to the requisite number of districts.
Production of a Summary Description and Maps
After the districts have been formed, a summary description of the redistricting plan must be produced. This description usually consists of a list of the geographic components of each district, a map of the district plan, and a statistical summary of the districts using selected population and possibly political data. This information may be used to evaluate the redistricting plan on a variety of levels, such as equal population, and is needed to implement the plan for election purposes.
