Opinion ID: 6501056
Heading Depth: 3
Heading Rank: 5

Heading: Other measures of partisan bias

Text: {¶ 52} In Adams, we credited expert analysis showing that the original plan unduly favored the Republican Party and disfavored the Democratic Party. __ Ohio St.3d __, 2022-Ohio-89, __ N.E.3d __, at ¶ 63-66. Petitioners have presented similar evidence showing that the March 2 plan likewise unduly favors the Republican Party. {¶ 53} Dr. Rodden concluded that a 3 percent statewide shift in favor of Democrats (bringing them to 50 percent of the statewide vote) would lead to Democrats winning, at most, five seats (i.e., 33 percent of the seats) under the March 2 plan. A 3 percent shift in favor of Republicans (bringing them to 56 percent of the statewide vote) would lead to Republicans winning 13 seats (i.e., 87 percent of the seats). Dr. Rodden also calculated that the March 2 plan has an 6. The Reock score is a method accepted by political scientists to measure the compactness of a district. 21 SUPREME COURT OF OHIO efficiency gap of 10 percent, which he says is relatively high in comparison to alternative plans he considered.7 {¶ 54} Dr. Rodden further points out that the March 2 plan treats Republican and Democratic incumbents differently. Of 12 Republican incumbents, ten are in safe Republican-leaning districts, one is in a nominally Democraticleaning district that retains about 70 percent of the population of his previous district, and one did not seek reelection. By contrast, of the four Democratic incumbents, two are in safe Democratic-leaning districts, one is in a district with a bare Democratic majority with only about half of the residents of the new district having been residents of her previous district, and one did not seek reelection. {¶ 55} Finally, Dr. Warshaw submitted three charts comparing the congressional-district plan that was in effect from 2011 through 2020, the invalidated plan, and the March 2 plan. Applying several social-science metrics to a variety of data sets, Dr. Warshaw shows that the March 2 plan is nearly as biased as last decade’s plan and the invalidated plan. This evidence supports the conclusion that the March 2 plan unduly favors the Republican Party.