Here are the efficiency gaps for the 2016 election in states with nine congressional seats. The closer to zero, the more closely election outcomes reflected statewide vote totals.
|Seat split||Efficiency gap||Favored party||Excess seats|
Source: Associated Press
Indiana elected one more Republican member of Congress and five more GOP state representatives than might have been expected last year, according to an analysis by The Associated Press.
AP combed through 2016 voting data to see how closely election results in state and federal legislative districts followed statewide vote totals. Wide gaps between a political party's share of the state vote and its number of elected candidates suggest gerrymandering – the drawing of districts to benefit one party over the other.
AP produced an “efficiency gap” percentage for each state, based on a 2014 formula developed by a law professor at the University of Chicago and a researcher at the nonpartisan Public Policy Institute of California. A zero percent gap means election outcomes adhered perfectly to statewide voting patterns.
Nearly 59 percent of Hoosier voters chose Republican congressional candidates in last year's election, when the GOP captured seven of nine seats. Indiana's efficiency gap was 10.6 percent, which is the percentage of excess seats Republicans won beyond what would be expected based on the GOP's district average vote share. Multiply the excess seat rate by the number of seats, as AP did, and you get 0.95 excess seats won by Republicans.
AP's numbers indicate that Hoosiers should have elected six Republicans and three Democrats to the U.S. House. But the closest contest last year was in south-central Indiana's 9th District, where Republican Trey Hollingsworth defeated Democrat Shelli Yoder by more than 44,000 votes.
For Indiana to add a Democratic U.S. House seat, largely Democratic Indianapolis, by far the state's most populous city, would have to “get chopped up” into another district, said IPFW political scientist Andrew Downs. Most of Indianapolis is in the 7th Congressional District.
“If all of the D's or all of the R's are concentrated in one part of a state, even though the efficiency score that comes out of this suggests that there should be one, two, three, four, 10 more seats in that party's control, you can't draw the boundaries that way, because the people are too concentrated in one area,” Downs said.
Indiana's gap might have been smaller had Republicans run somebody to challenge Democratic Rep. Pete Visclosky in the northwest 1st District. The district is safely Democratic, but any smattering of GOP votes would have boosted the party's total share of the state vote. On the other hand, the GOP might have lost vote share had Democrats fielded more competitive candidates in the northeast 3rd District and the southeast 6th District.
Most states with a similar number of congressional districts had much smaller gaps than Indiana's. In Arizona, for instance, 51.6 percent of voters chose Republican candidates, and the state elected five Republicans and four Democrats, resulting in a 2.3 percent efficiency gap. Tennessee had a 0.02 percent gap – tied for the second smallest in the nation – despite electing seven Republicans in nine districts.
The gaps in Washington, Missouri, Massachusetts and Minnesota also were smaller than Indiana's, while those in Maryland and Wisconsin were slightly larger.
In the AP analysis of last fall's elections for state Houses, Indiana's 4.8 percent efficiency gap put it in the middle of the pack among the 11 states with roughly 100 state representatives apiece. The gap translated to an additional 4.76 Republican representatives. Hoosiers elected 70 Republicans and 30 Democrats to the House last year. The AP analysis suggests a 65-35 split would have better reflected statewide voter preferences.
Again, Tennessee showed the best representative-to-state-vote balance, with a 1.5 percent gap. On the other end of the scale were Michigan at 10.3 percent and Wisconsin at 9.8 percent, with both states favoring Republicans.
Downs, director of the Mike Downs Center for Indiana Politics at IPFW, said the nonpartisan goals of redistricting are geographically compact, contiguous districts that keep “communities of interest” together. But population migration trends can throw things off kilter in a state, he said.
“It's quite possible the reason there are states with higher or lower efficiency scores is because of where people have chosen to live,” Downs said. “If we are going to respect the concept that communities of interest should be kept together, then you're not going to divide up a particular community in a way that might allow for a different party to win a seat somewhere.”
Indiana's larger cities are so far apart from one another that most congressional districts are going to be a blend of urban Democrats and rural Republicans, he said.
“You put nine boundaries in Indiana, and you are going to mix urban and rural somewhere,” Downs said. “Evansville, Fort Wayne, South Bend, the northwest – there's going to be some agriculture in with those clearly urban areas.”
Indiana legislators redraw congressional and state legislative districts every 10 years, with the next redistricting coming after the 2020 census. A General Assembly interim study committee recommended last year that the task be handed to an independent redistricting commission, as a half-dozen other states have done. Legislation creating such a commission failed to gain traction this year in the Republican-run General Assembly.
Sheila Suess Kennedy, a law and public policy professor at IUPUI, was a member of the study committee and is a proponent of an independent redistricting commission.
“You have a red state like Indiana, we're still going to be a red state,” Kennedy said in reference to the color associated with Republican-leaning states and districts. Blue is the color associated with Democratic regions.
“It isn't that you are going to turn Indiana blue or Maryland red,” she said about independent redistricting. “Are you going to elect more responsive kinds of people, people who are willing to listen to constituents who aren't in their base?
“Right now in Indiana, our legislators choose their voters. We're supposed to choose them, not the other way around,” Kennedy said.
The AP data analysis offers mixed results on the states with independent or nonpartisan redistricting commissions, including Iowa, where the legislature has final approval for maps. Four states had small efficiency gaps in their 2016 congressional elections, but Idaho's was 13.7 percent and Iowa's was 15.6 percent. And only California had a small gap in state House elections.
Downs noted that in the last round of redistricting, Republican state lawmakers in Indiana said they wanted to try to avoid splitting too many counties across congressional and state legislative districts. But county lines do not define a community of interest, he said.
“The reality is, the people in Scipio Township don't have a lot in common with Wayne Township” in the center of Allen County, Downs said. “While Allen County can be defined as a community of interest, Scipio Township or Monroe Township may have more in common with parts of DeKalb and Adams than the rest of Allen.”
Scipio and Monroe are largely rural townships in the northeast and southwest parts of Allen County, respectively.
“As much as government affects us on a daily basis, the reality is it's the people I'm living next to and interacting with on a regular basis that really create that definition of political boundaries,” Downs said.