How to Fix Gerrymandering – Slate Magazine
This week, the Supreme Court agreed to take up the case of Gill v. Whitford, whose plaintiffs claim the electoral boundaries drawn up by the GOP-controlled Wisconsin legislature constitute a gerrymander so extreme as to deny them their full ability to vote. The maps in my home state were engineered with merciless precision to ensure a lasting Republican majority in a place whose recent voting practices have oscillated within a narrow purple band. This is surely unfair; the courts will decide whether it’s unconstitutional as well.
It won’t be easy. Redistricting is an unholy snarl of law, politics, and math, and there’s probably no single person who understands it from top to bottom. (But some of us are trying: A group of researchers at Tufts University is organizing a series of conferences in which citizens and scientists are hashing some of these issues out; I’m hosting one in Madison, Wisconsin, in October.)
Here’s one reason redistricting is such a difficult problem. In Wisconsin, two of the major population centers, Madison and Milwaukee, are dominated by Democrats, while only one (centered on, yes, crucial Waukesha County) is similarly Republican-heavy. The rest of the state is more moderate but leans mildly Republican overall. It’s not totally crazy, then, for a legislative map to consist of a few heavily Democratic districts in the big cities and many slightly Republican ones elsewhere. Such a map wouldn’t necessarily be evidence of biased, partisan gerrymandering—in some measure, it’s just a consequence of the state’s geography.
Wisconsin claims its map is just such an organic, free-range gerrymander. University of Michigan political scientist Jowei Chen sees it differently. Chen generated 200 random maps algorithmically, using party-neutral methods. Not one of them was as GOP-friendly as the one Wisconsin is using—not even close.