The Constitution of North Dakota requires the Legislative Assembly to redistrict itself following each federal decennial census (Article IV, Section 2). However, legislative districts remained unchanged between 1931 and 1963. For details of redistricting from statehood to October 1981, refer to the University of North Dakota Bureau of Governmental Affairs publication Legislative Reapportionment in North Dakota: From Statehood to Present. (Special Report No. 62) In the June 1960 primary election, voters approved a constitutional amendment that:
- Froze the senatorial districts as they stood under the 1931 plan.
- Stipulated that there be at least one House member for each senatorial district and at least one House member for each county in those districts encompassing more than one county. It also provided that remaining members of the House be apportioned by the Legislative Assembly on a population basis after each federal decennial census.
- Established a commission composed of the Chief Justice of the North Dakota Supreme Court, the Attorney General, the Secretary of State, and the majority and the minority leaders of the House to produce a redistricting plan if the Legislative Assembly did not. Such a plan was due within 90 days after the Legislative Assembly adjourned.
When the 1961 Legislative Assembly did not adopt a redistricting plan, the constitutionally designated commission did so. The North Dakota Supreme Court held that plan unconstitutional. The court also ruled that the special commission’s authority to redistrict expired 90 days after the Legislative Assembly adjourned. The court gave the 1931 plan effect until the 1963 legislative session.
In 1963, the Legislative Assembly adopted a redistricting plan. The United States District Court held the 1963 plan unconstitutional as a violation of the equal protection clause of the 14th Amendment to the United States Constitution. The court also held the 1960 constitutional amendment and the 1931 plan unconstitutional. The court concluded there was not enough time to put together a constitutionally valid plan for the 1964 election and ordered the election to proceed under the 1963 plan. The 1965 Legislative Assembly adopted a redistricting plan. The federal district court declared that plan unconstitutional, modified a proposed plan that had been recommended by the Legislative Research Committee’s interim 1963-64 Constitutional Revision Committee and made it the plan for the state.
After no redistricting plan was adopted by the 1971 Legislative Assembly, the federal district court was asked to declare the 1965 plan unconstitutional and to issue its own plan. The court appointed three special masters to prepare a plan valid for the 1972 election.
The 1973 Legislative Assembly passed a redistricting plan and overrode the Governor’s veto of the plan. However, the plan was then referred and defeated by the electorate at a special election on December 4, 1973.
In 1974 the federal district court declared the plan adopted by the court in 1971 to be the permanent redistricting plan. The court’s decision was appealed, and in 1975 the United States Supreme Court ruled the 1971 court plan unconstitutional. The 1975 Legislative Assembly adopted a modified version of the plan developed by the federal district court. The district court subsequently ruled the 1975 plan unconstitutional. The court then appointed a special master who formulated a plan that was adopted by the court. Until 1981 the state followed this plan.
In the first reconvened session ever, the Legislative Assembly met in November 1981 to adopt a redistricting plan. The new plan provided for 53 districts with a total of 159 legislators. Two multisenator or double districts were created to blend the Grand Forks Air Force Base with a section of Grand Forks (Districts 17-18) and to do the same with Minot Air Force Base and Minot (Districts 40-50). All senators in odd-numbered districts ran for office in 1982. Any senator in an even-numbered district elected in 1980 whose district now contained new geographic area ran for a two-year term if that area was not in the district in the 1980 election and the area had a 1980 population of more than 2,000.
In November 1991, the Legislative Assembly met in a special legislative session and reduced the number of districts from 53 to 49 and the number of legislators from 159 to 147. The double districts in Minot and Grand Forks were eliminated. In the special legislative session held November 26-30, 2001, legislators met to redraw legislative district boundary lines following the decennial census. As a result, the number of districts fell from 49 to 47, bringing the number of legislators to 141, the lowest total since the 1903-1907 legislative sessions, which had 140. The 2001 bill (Senate Bill No. 2456) eliminated two Senate and four House seats. Its provisions brought the potential for races among incumbents in eight districts during the general election of 2002.
In November 2011, the Legislative Assembly met in a special legislative session to redistrict based on the 2010 census.