Math tools send legislators back to the drawing board
On January 9, 2018, a trio of federal judges made history when they ruled that the boundaries of North Carolina’s congressional voting districts gave an unfair advantage to Republican candidates. It was the first case in the nation in which a federal court had declared congressional maps unconstitutional because of intentional bias in favor of one party. The case was all the more remarkable because the court decision relied in part on mathematical tools that can probe the practice of gerrymandering—the drawing of voting districts to give an intentional advantage to one party.