In 2015, Ohio voters approved a state constitutional amendment that reformed the process for drawing district lines for the state legislature. Previously, state legislative redistricting had been managed by a five-member Apportionment Board, consisting of the governor, the secretary of state, the state auditor, and one member of the state legislature from both parties. New district lines only required a simple majority vote to enter into effect. The amendment, Issue 1 on the 2015 ballot, enlarged (and renamed the board to the Ohio Redistricting Commission) the Apportionment Board by two members by adding a member of each party from the state legislature. Issue 1 also reformed the procedures of the board, particularly how it approves district maps. The Commission must now have votes in favor of a map by at least two members of the minority party for the district maps to be in force for a full ten years. However, if this requirement is not met, then the district maps will be in force for only four years and new maps will be drawn at the end of that time period.
Beyond adjusting the approval process, Issue 1 changed the criteria the Commission must use in drawing state legislative districts in order to combat some fairly popular gerrymandering tactics used across the United States. Issue 1 requires the Commission to split as few municipalities as possible in drawing lines and must justify any municipality or county splits when presenting their plan to the state legislature. The amendment forbids a districting plan from favoring one party and the districts must be compact. The Commission should draw districts such that the proportion of districts that favor any party should closely match the statewide preference of Ohio voters. Additionally, the Commission must hold at least three public hearings across the state.