OH HJR12

Establishes a seven-member Ohio redistricting commission consisting of the governor, auditor of state, secretary of state, and four members appointed by legislative leaders to draw General Assembly district boundaries every ten years.

Requires four affirmative votes including at least two members from each of the two largest political parties to adopt any General Assembly district plan, with bipartisan co-chairpersons appointed jointly by party leaders.

Mandates 99 House districts and 33 Senate districts with population ratios within 95-105 percent of the state average, composed of contiguous territory using county, municipal corporation, and township boundaries where feasible.

Requires Senate districts to be composed of three contiguous House districts and includes provisions prioritizing minimal splits of counties and municipalities while maintaining population equality standards.

Includes a fallback process where if the commission cannot adopt a plan by September 1 of redistricting years (ending in "1"), it may adopt by simple majority, with such plans remaining effective for two House election cycles or until the next redistricting year.

Takes effect January 1, 2021, if approved by Ohio voters and repeals existing Article XI redistricting provisions.