The Supreme Court today will hear arguments in Gill v. Whitford, a political gerrymandering case out of Wisconsin.
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Political gerrymandering, which refers to the act of drawing legislative districts for partisan advantage, is a common practice. This case asks when the use of politics in redistricting crosses the line from ordinary partisanship to something that is so excessive as to be unconstitutional.
The Supreme Court has said courts can decide these cases (there are some who argue that the cases are simply too political for courts to decide) but has never explained how to decide when partisanship crosses the line.
What is the case?
In 2011, Wisconsin’s Republican governor signed Act 43, which allowed for a redistricting of the state. The move also appeared to give Republicans an advantage in the state's elections.
William Whitford, a University of Wisconsin Law School professor emeritus and the lead plaintiff in the case, argues the newly created map does not accurately reflect Wisconsin’s electorate.
"Wisconsin’s Assembly ... bears no resemblance to its evenly split electorate. In 2012, Republicans won a supermajority of 60 seats (out of 99) while losing the statewide vote. In 2014 and 2016, Republicans extended their advantage to 63 and 64 seats, respectively, even though the statewide vote remained nearly tied. Republicans thus wield legislative power unearned by their actual appeal to Wisconsin’s voters. This pro-Republican skew is no accident,” he says.
According to Beverly Gill, the state election board's chair, “Act 43’s districts are consistent with the prior court-drawn maps.”
How did the case make its way to the Supreme Court?
A lower court found that the GOP-drawn Wisconsin map was unconstitutional because it was drawn with partisan intent, had a partisan effect and had no valid justification. In measuring the impact of the challenged map, the court relied on part on a formula called the "Efficiency Gap," which compares each side's "wasted" votes.
How could the court rule and what's the potential impact?
If the Supreme Court agrees that this Wisconsin plan was unconstitutional, it would mark a major change, both in constitutional law and in the way in which redistricting is carried out in virtually every state.
When should we expect an answer?
It seems highly likely that the four liberal-leaning justices will vote to affirm the lower court opinion invalidating the plan. It seems equally clear that the four conservative-leaning justices will vote to reverse the lower court.
The big question is what Justice Kennedy will do. He wrote a significant separate concurring opinion in a 2004 redistricting case, and again in 2006, making clear that he does believe some redistricting may violate the Constitution, but that no one has yet crafted a workable standard for courts to apply. The plaintiffs in this case hope that they've finally developed a test that will satisfy Justice Kennedy; we'll have to wait for the opinion, which is likely to come this winter or early spring.