The 2018 midterms will be fiercely fought, with a focus on control of the U.S. House after years of Republican dominance. At the same time, the U.S. Supreme Court will likely hear a challenge to partisan gerrymandering in Gill v. Whitford later this year. And both parties gearing up for the new national redistricting cycle starting in 2021. Congressional maps are back in the political spotlight.
Today, a new report from the Brennan Center for Justice at NYU School of Law finds that extreme partisan bias in congressional maps account for at least 16-17 Republican seats in the current Congress –a significant portion of the 24 seats Democrats would need to gain control of the House in 2020 – and that only a small number of swing states account for the vast majority of this partisan skew.
Extreme Maps, the first in-depth report to use data from the 2016 election as well as the 2014 and 2012 cycles, focuses on the most egregious map-drawing abuses. The congressional maps in question have high levels of “partisan bias” – the degree of systematic advantage one party receives over another in turning votes into seats – under at least three widely accepted statistical measures.