On June 7, the Wisconsin voters who sued their state over its partisan gerrymander, and who won their case in a three-judge U.S. District Court, filed this brief in the U.S. Supreme Court. The voters hope that the U.S. Supreme Court (which won’t decide whether to hear the state’s appeal until October 2017 at the earliest) will not stay the lower court decision. If no stay is granted by the U.S. Supreme Court, then the Wisconsin legislature will be forced to redistrict the legislative districts this year, or else the U.S. District Court will do it this year.
The U.S. Supreme Court will consider whether to grant a stay at its June 8 conference, but the news from that conference won’t be announced until June 12. Thanks to Barry Burden for the link.
The Chen study cited by the brief illustrates that the “Efficiency Gap” does not measure what it purports to measure. If we look at Figure 2, we will notice that the results line up in columns – it is not a continuous function.
If we compare Figure 2 with Figure 5, we will see that the two share the identical pattern (the X axis is flipped, in Figure 2 more Republican results are to the left, while in Figure 5, the more Republican results are to the right.
The efficiency index is in reality a measure of proportionality. The fuzziness of the columns in Figure 2 is solely due to the variation in the number of votes cast in a district. According to the proponents of the Efficiency Gap, half the votes in a district are “wasted”. If there are more votes cast, there are more wasted votes.
Thus according to advocates of the Efficiency Gap, a plan could be made fairer or unfairer by placing more children, non-citizens, felons, low-participation voters in some districts – which hardly seems consistent with the ideal of one voter, one vote.