Arizona Redistricting Commission chooses competitiveness metrics

The Arizona Independent Redistricting Commission has selected the tools it will use to determine whether the new congressional and legislative districts it draws are competitive.

On Tuesday, the commission chose two metrics to determine competitiveness. One will use the results from statewide races over the past three election cycles to determine how close the average vote in a proposed district would have been, while the other will use those measurements to determine how often the proposed districts would have changed hands between Democrats and Republicans. 

The commission chose a “basket” of statewide races from the past three election cycles: 2016, when Republicans won the only statewide races on the ballot in Arizona; 2020, when Democrats won all of the statewide races; and 2018, the last time Arizona’s statewide offices were up for election, which was a mix of Democratic and Republican victories.

The IRC excluded the “outlier” races of the 2016 U.S. Senate contest and 2018 gubernatorial contest, when Republicans John McCain and Doug Ducey notched double-digit victories. They also omitted elections for Corporation Commission because those races featured multiple seats that were up for grabs, with Democrats and Republicans putting up different numbers of candidates.

Past election results will be considered using two ranges. The first will consider a district competitive if the average difference between the two parties is seven percentage points — a result between 53.5% and 46.5%. The second uses a narrower range of 48% to 52%, which mapping consultant Doug Johnson considered “highly competitive.”

Democratic Commissioner Shereen Lerner proposed the narrower range, while Republican David Mehl suggested a wider range favored by the redistricting experts who have spoken to the commission recently. 

“If we can look at both of those and see how things land, we can evaluate later on and see how it’s going,” Lerner said. 

Redistricting experts generally recommend determining competitiveness based on voter registration numbers, which can paint an inaccurate portrait of an area’s partisan voting tendencies. That problem becomes exacerbated when there are large numbers of independent voters, who make up about a third of Arizona’s electorate.

Competitiveness is one of the six criteria that the Arizona Constitution directs the commission to use when drawing new maps, but with the caveat that it should only favor competitiveness “where to do so would create no significant detriment to the other goals.”

“How do we measure significance on this to know whether or not there is a significant detriment here?” Lerner asked.

“There’s a huge element of commissioner judgment on that,” responded Johnson, who was a consultant for the 2001 commission that spent years in court defending its maps over allegations that it didn’t properly consider competitiveness.

Commissioner Erika Neuberg, the AIRC’s independent chairwoman, emphasized that the new metrics aren’t written in stone and may be subject to future revisions.

The decision on competitiveness comes as the commission prepares to begin the work of drawing new district boundaries after months of focus on staffing, public input and other issues. The commission is getting a late start to the actual mapmaking part of their job due to a pandemic-induced delay in census data. The U.S. Census Bureau will release the data that states need for redistricting on Thursday.

Once it has the census data in hand, the commission will start the process of drawing new districts with a “grid map” that wipes the previous map clean and creates a starting point of nine congressional districts and 30 legislative districts crafted based on equal population alone, as well as respect for preexisting county boundaries, where possible. Once that’s done, the commission will adjust those lines based on the six criteria in the state constitution.

The commission voted on Tuesday to use the state’s “township median” — a central geographical point located at the intersection of 19th Avenue, Grand Avenue and McDowell Road in Phoenix — as the starting point for the grid map. From there, it will work clockwise around the rest of the state.