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Gerrymander map

This map, among the exhibits submitted with a lawsuit challenging Wisconsin's 2011 legislative map, shows the differences in legislative districts and representation under different scenarios, including a plan proposed in the lawsuit applied to 2012 election results.

A federal trial began Tuesday in a case examining Wisconsin's legislative district maps and whether Republicans intended to disenfranchise Democratic voters by concentrating them into fewer districts.  

The day's testimony included a GOP consultant who engineered the map lines using sophisticated mathematical models as well as with a legislative aide who worked on the maps.

Before a three-judge panel, attorneys for the plaintiffs — a group of 12 Democrats — outlined the three-part legal test they will use to show that the state's legislative district maps, enshrined in 2011 Act 43, violate the U.S. Constitution. Republican lawmakers redrew the lines for 132 Legislative districts in 2011 and subsequently scored significant electoral wins in the next election, further entrenching a majority advantage in the Legislature.

States are required to redraw their districts every 10 years to keep pace with population changes as reflected in the U.S. Census. 

Attorney Nicholas Stephanopoulos, representing the plaintiffs, called the maps one of the "worst gerrymanders in modern American history” and said "It was designed to be an egregious gerrymander. That goal has been fully accomplished in the elections since the plan has been accomplished and that plan will continue to be accomplished for the rest of the decade.”

He called the redistricting maps a "dramatic change that was accomplished through ever more systematic tracking and packing of Democratic voters.”

Stephanopoulos outlined a three-pronged case focused on "discriminatory intent," "discriminatory effect" and "justification." His case relies largely on a mathematical test called "the efficiency gap" to look at whether the districts allow votes for Republicans and Democrats to have equal weight.

Assistant Attorney General Brian Keenan criticized the "efficiency gap," which issues scores to each districts predicting which party will win them. Keenan said the metric's calculations were not correct and was not a valid way to predict the outcome of elections. 

The scores “are far from magic crystal balls that predict the future,” he said. "These are just educated guesses."

How legislative districts are drawn are often predictive of which party's candidates can win there.  Districts with higher concentrations of Republican voters will increase the likelihood that a Republican will win that district and gain a seat in the Legislature. Critics of the current legislative map say Republicans purposefully parsed the state along partisan lines with the aim to create more districts that Republicans can win.

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Officials who developed the map explained Tuesday how they used precise, precinct voting data from 2006, 2008 and 2010 to draw new maps and ran statistical regressions and correlation models to predict electoral outcomes for newly created districts. 

Keith Gaddie, a political science professor at Oklahoma University, who was hired by Republican lawmakers to engineer the maps, explained how he used precinct voter data to create statistical regression models and correlation illustrations to predict how new district could affect election outcomes. He worked with attorneys at Michael Best & Friedrich in a closed office where security was tight. Only certain people were allowed to see certain versions of map drafts, according to testimony. Gaddie said he did not communicate or work with lawmakers on the draft, other than Senate and Assembly leadership. 

“My job was do devise measures, measures of compactness, integrity of counties," he said. Gaddie said he was charged with "disentangling minority districts in Milwaukee" and crafting a Latino majority Assembly district for Milwaukee County. 

Adam Foltz, an aide to former Assembly Speaker Jeff Fitzgerald, R-Horicon, was charged with drawing the new maps for lawmakers at the time, also testified Tuesday.

The trial is scheduled to last four days, concluding on Friday.

Katelyn Ferral is The Cap Times' public affairs and investigative reporter. She joined the paper in 2015 and previously covered the energy industry for the Pittsburgh Tribune Review. She's also covered state politics and government in North Carolina.