ASA, AMS Issue Joint Statement on Drawing of Voting Districts, Partisan Gerrymandering

The American Statistical Association and Council of the American Mathematical Society (AMS) issued a joint statement to inform discussions and planning around the drawing of voting districts as we approach the 2020 census. This marks the first time in recent history the two organizations have issued a joint statement of broad interest to the American public.

The statement is organized around the following three facts:

• Existing requirements for districts generally do not prevent partisan gerrymandering.
• It has become easier to design district plans that strongly favor a particular partisan outcome.
• Modern mathematical, statistical, and computing methods can be used to identify district plans that give one of the parties an unfair advantage in elections.

“While these points may be common knowledge in some circles, it’s important they be stated by objective and respected authorities like the AMS and the ASA and for them to be more widely known in the redistricting discussions around the 2020 Census,” noted 2018 ASA President Lisa LaVange.

AMS President Ken Ribet said, “Our community is poised to play a central role in ongoing discussions about methods for creating voting districts and the evaluation of existing and proposed district maps. It has been a pleasure for me to observe the recent explosion in interest in this topic among colleagues and students in mathematics and statistics. I anticipate that the new statement by the ASA and AMS Council will lead to increasing transparency in the evaluation of districting methods.”

“Statistical and mathematical standards and methods can be very helpful to inform decision-makers and the public about partisan gerrymandering,” remarked the statement’s main architect, Jerry Reiter, chair of the ASA Scientific and Public Affairs Advisory Committee. “The statement acknowledges the value of partisan asymmetry as a standard, and it highlights some methods for measuring partisan asymmetry. The statement does not endorse any one method, as ultimately this issue is determined by policymakers and the courts.”

In issuing the statement, the two societies also offer to connect decision-makers and policymakers with mathematical and statistical experts.