Special Lecture

The US political system is built on representatives chosen by geographically localized regions. This presents the government with the problem of designing these districts. Every ten years, the US census counts the population and new political districts must be drawn. The practice of harnessing this administrative process for partisan political gain is often referred to as gerrymandering.

How does one identify and understand gerrymandering? Can we really recognize gerrymandering when we see it? If one party wins over 50% of the vote, is it fair that it wins less than 50% of the seats? What do we mean by fair? How can math help illuminate these questions?

How does the geopolitical geometry of the state (where which groups live and the shape of the the state) inform these answers ?

The use of a collection of “neutral”, computer-generated, redistricting maps is quickly becoming the standard for identifying Gerrymandering and understanding the ways it is achieved. Several teams have used these ideas in advising governors and legislatures as well as in several court proceedings. The Duke group has been involved in several cases that have lead to the redrawing of all of the federal and state-level redistricting maps for the 2020 elections. We are currently involved in discussions around the 2021 redistricting cycle in a number of states.

For me, these questions began with an undergraduate research program project in 2013 and has led me to testify twice in two cases: Common Cause v. Rucho (that went to the US Supreme Court) and Common Cause v. Lewis. This work has partially resulted in the redrawing of the NC State Legislative district maps and NC congressional maps. The resulting new maps will be used in our upcoming 2020 elections.

In the remedy phase of North Carolina v. Covington, Greg Herschlog from the Duke group address the question if attempts to satisfy the VRA alone explained the observed level political packing and cracking.

This is a story of interaction between lawyer, mathematicians and policy advocates. The legal discussion has been increasingly informed by the mathematical framework. And the mathematics has been pushed to better include to the policy. The back and forth has been important to find ways to effectively inform the policy makers and courts to the insite the analyses provide. The problem of understanding gerrymandering has also prompted the development of a number of new computational algorithms which come with new mathematical questions.

The next round of redistricting analysis will necessarily need to be more refined and nuanced. There is also the opportunity to be less reactive. There are opportunities to try to influence the process by which new maps are drawn before turning to the courts. There is also the possibility to direct the conversation by showing the effect more fully considering factors such as communities of interest, incumbency or proposed procedural elements of laws.

This presentation reflects joint work Gregory Herschlag and a number of other researchers including Math, Policy and Law Faculty and many undergraduates, graduate students, and a few high school students.