On May 24, 2016, a three-judge panel in Federal Court will address the question of whether the Wisconsin legislatureʼs 2011 redistricting plan is unconstitutionally partisan. Twelve Wisconsin democrats have sued the Wisconsin Department of Justice alleging that Republican state redistricting was unconstitutionally partisan and “one of the worst gerrymanders ever.”

Gerrymandering is the manipulation of district boundaries for the political advantage of a particular party. The word was coined in 1812 when Massachusetts Governor Eldridge Gerry redrew district lines in Boston to favor his party. The district created had a bizarre shape that resembled a salamander. Gerry and salamander combine to form Gerrymander.

Over the last 200 years gerrymandering has been a tried and true political method. Many strangely shaped districts, not only salamanders, have served the interest of partisan politics. Until recently North Carolina Congressional District 14 was over 80 miles long and in places only as wide as the interstate it followed. The saying was that “If you drove down the Interstate with both car doors open youʼd kill most of the people in the district.”

How district lines are drawn can influence election results in many ways. Common methods are packing and cracking. In “packing” similar voters are packed together in a single district, removing their influence from other districts. In the illustration above, the fourth map shows how packing can work. Notice that most of the blue squares are bundled into two districts, each of which has only one red square in it.

In “cracking” blocks of voters are broken apart and distributed in other districts to dilute their voting strength as much as possible. You can see the effects of cracking most clearly in the third map above. Red squares are broken up into blocks of four, diluting their voting strength in every district.

Political boundaries are usually redrawn every ten years in response to census data. In most states the state legislature controls the redistricting process. Manipulating district boundaries for partisan purposes, or gerrymandering, is not illegal unless the plan violates the Voting Rights Act.

In 2011 Wisconsin Republicans controlled all branches of state government — the assembly, the senate and the governorship. They thus had complete control of the redistricting process, which was carried out in strict secrecy using private lawyers. Only one public hearing was held before the map was passed by the legislature and signed by Governor Walker.

The redistricting map was greeted by a torrent of objections and spawned myriad lawsuits. A large number of documents were lost and a hard drive with redistricting data was destroyed. A judge who had unsuccessfully tried to access documents chastised “the all but shameful attempt to hide the redistricting process from public scrutiny.”

A Latino district that had been split (as a result of cracking) was restored by court order, but otherwise the district lines drawn by the legislature in 2011 formed the basis of the electoral districts for the 2012 and 2014 elections. The map was attacked by Democrats as an example of extreme gerrymandering. Although the districts it created lacked bizarre shapes, the districts were drawn so as to strengthen the Republican hold on government. For instance, the liberal suburb of Shorewood was removed from the state senate district of conservative Alberta Darling — in a clear example of cracking — to strengthen her against a possible recall election. Kenosha and Racine, both Democratic, were packed together, enabling a strong Republican district to be formed to the west.

In July 2015 a group of 12 Democratic Wisconsin voters sued the state Department of Justice over “unconstitutional and profoundly undemocratic” gerrymandering that diluted the voting power of certain voters based on their political beliefs. To support this allegation the suit stated that even though Democrats won more than 50% of the votes cast statewide for the assembly in the first election after redistricting (2012), Republicans captured 60% of the assembly seats (60 of 99 ).

In November 2015 and again in March 2016 the Wisconsin Department of Justice sued in Federal Court for the lawsuit to be dismissed. Both times the courts ruled against dismissal, allowing the case to proceed. The trial set to begin May 24, 2016 in Federal Court will be heard by a three-judge panel, including one Federal Appeals Court judge. If a decision is appealed the case will go directly to the United States Supreme Court.

It has been hard to achieve legal remedy for the problem of gerrymandering. Courts hesitate to rule on it, and in fact no court has ever been struck down a redistricting map because of it. A key problem is the need to find a number that will quantify the effect of changing district boundaries on the power of a vote. Without a reliable quantification of the effect of gerrymandering there is no valid way to compare two maps or to determine at what point a scheme is unconstitutional.

In the case to be heard May 24, the plaintiffs will for the first time be using a calculation devised by legal scholars called the “Efficiency Gap.” The Efficiency Gap is calculated for both parties from the results of the first election after district boundaries have been redrawn. The number is the percent of “wasted votes” out of all votes cast, with wasted votes being those over the number needed to win, plus all losing votes. The metric developed by these scholars proposes that the maximum acceptable E.G. should be less than 7% for the losing party. For the 2012 election the E.G. for Wisconsinʼs Democrats was 13%, indicating significant gerrymandering effects.

The lawsuit against the Department of Justice has ramifications not only for Wisconsin but for the rest of the country. If the court accepts the Efficiency Gap as a yardstick for unconstitutional gerrymandering, the legal landscape surrounding redistricting will be transformed.

Acknowledgement: Pat Slutske, “When Salamanders Rule Voters Lose” Grass Roots North Shore Newsletter July 21, 2015