Montana Code Annotated
Part 1. Districting and Apportionment Commission
5-1-115. Redistricting criteria

5-1-115. Redistricting criteria. (1) Subject to federal law, legislative and congressional districts must be established on the basis of population.
(2) In the development of legislative districts, a plan is subject to the Voting Rights Act and must comply with the following criteria, in order of importance:
(a) The districts must be as equal as practicable, meaning to the greatest extent possible, within a plus or minus 1% relative deviation from the ideal population of a district as calculated from information provided by the federal decennial census. The relative deviation may be exceeded only when necessary to keep political subdivisions intact or to comply with the Voting Rights Act.
(b) District boundaries must coincide with the boundaries of political subdivisions of the state to the greatest extent possible. The number of counties and cities divided among more than one district must be as small as possible. When there is a choice between dividing local political subdivisions, the more populous subdivisions must be divided before the less populous, unless the boundary is drawn along a county line that passes through a city.
(c) The districts must be contiguous, meaning that the district must be in one piece. Areas that meet only at points of adjoining corners or areas separated by geographical boundaries or artificial barriers that prevent transportation within a district may not be considered contiguous.
(d) The districts must be compact, meaning that the compactness of a district is greatest when the length of the district and the width of a district are equal. A district may not have an average length greater than three times the average width unless necessary to comply with the Voting Rights Act.
(3) A district may not be drawn for the purposes of favoring a political party or an incumbent legislator or member of congress. The following data or information may not be considered in the development of a plan:
(a) addresses of incumbent legislators or members of congress;
(b) political affiliations of registered voters;
(c) partisan political voter lists; or
(d) previous election results, unless required as a remedy by a court.
(4) In the development of congressional districts and under the authority granted to the legislature by Article I, section 4, of the United States constitution, a congressional districting plan is subject to the Voting Rights Act and must comply with the following criteria, in order of importance:
(a) The districts must be as equal as practicable.
(b) District boundaries must coincide with the boundaries of political subdivisions of the state to the greatest extent possible. The number of counties and cities divided among more than one district must be as small as possible. When there is a choice between dividing local political subdivisions, the more populous subdivisions must be divided before the less populous, unless the boundary is drawn along a county line that passes through a city.
(c) The districts must be contiguous, meaning that a district must be in one piece. Areas that meet only at points of adjoining corners or areas separated by geographical boundaries or artificial barriers that prevent transportation within a district may not be considered contiguous.
(d) The districts must be compact, meaning that the compactness of a district is greatest when the length of the district and the width of a district are equal. A district may not have an average length greater than three times the average width unless necessary to comply with the Voting Rights Act.
History: En. Sec. 1, Ch. 3, L. 2003; En. Sec. 1, Ch. 546, L. 2003; amd. Sec. 1, Ch. 531, L. 2021.