Gerrymandering and the Efficiency Gap

You probably know about the Hillary Clinton popular vote lead. Less well known is the degree to which gerrymandering is affecting downballot races. For instance, in 2012, when Republicans won a 33-seat majority in the house? Democrats got 1.7 million more votes. It’s not our messaging that’s a problem, or even our turnout. It’s maps. (Anybody who is about to jump in with “but the party in power has always” – NO. This is very different in degree. Plus wrong is wrong no matter who did it.)

The Supreme Court has ruled this unconstitutional, repeatedly, because duh. It violates all kinds of equal protection promises in the law. The problem has been finding a standard, a test, that can be applied by different people with different ideologies and come to the same conclusion about whether or not a given map is too gerrymandered. It’s essentially the obscenity problem, or the art problem. At what point does something shift from pushing-the-envelope to illegal? “I know it when I see it” is insufficient for the courts.

We might finally have a test, and we might be able to get it in play in time for the redistrictings that will happen after the 2020 census (and be able to use it in legal challenges before then). This is IMPORTANT MATH Y’ALL. Big ups to math. If you have a fear of word problems, OVERCOME. Here’s the explanation of the formula, courtesy of Slate‘s Mark Joseph Stern:

Smith and the CLC believe they have found the right standard in the work of two scholars, Nicholas O. Stephanopoulos and Eric M. McGhee. This formula—called the “efficiency gap”—cites two types of “wasted votes” in the redistricting process: “lost votes” cast in favor of a defeated candidate, and “surplus votes” cast in favor of a winning candidate that weren’t actually necessary for the candidate’s victory. The efficiency gap is, in Stephanopoulos’ words, “the difference between the parties’ respective wasted votes in an election, divided by the total number of votes cast.”

This formula may sound like an oddly technical method for ensuring basic representational equality. When both Democrats and Republicans waste roughly the same number of votes, the efficiency gap is near zero. That means voters on both sides had a fair shot at securing their desired representation. When a party gerrymanders its opponents into the minority, however, it will “waste” fewer votes than its opponents, causing the efficiency gap to rise. A historical analysis of elections across from the country since 1972 suggests that an efficiency gap of 7 percent will entrench the majority party’s power until new maps are drawn. Wisconsin’s Republican-drawn gerrymander has an efficiency gap of 13 percent, meaning a huge number of Wisconsinites are currently deprived of their representational rights solely because they are Democrats.

Needless to say, this is also a pretty firm rebuttal to the idea that Republican control of state legislatures is a “mandate” that indicates the American people love their platform. Maps. It’s maps. It’s REDMAP.