State lawyers defending Wisconsin’s 2011 redistricting plan, which was called an unconstitutional partisan gerrymander by a federal court panel, filed their opening brief Friday with the U.S. Supreme Court, arguing that the high court should reject the lower court ruling and throw out a lawsuit brought in 2015 by a group of state Democratic voters. The Supreme Court in June announced that it would decide the case, and later set oral arguments for Oct. 3. The group of Democrats charges that the 2011 plan was designed to heavily favor Republican candidates in state legislative races, giving them a built-in advantage to retain a large majority of seats in Wisconsin’s legislative houses, despite statewide vote totals in presidential races that typically split nearly evenly between Republicans and Democrats.
The group said it has devised a means of measuring partisan gerrymanders, which the Supreme Court in the past has said was missing. Its measure, called the “efficiency gap,” shows how cracking (breaking up blocs of Democratic voters) and packing (concentrating Democrats within certain districts) results in wasted votes — excess votes for winners in safe districts and perpetually inadequate votes for the losers.
In its brief, the state argues that the Supreme Court has never found that any state legislature has engaged in unlawful partisan gerrymandering, and that the Democratic group has given the court no new redistricting principles or test.