When you're ill, medical professionals will run tests and make a diagnosis, gearing your medical treatment to what ails you. After all, heart attacks and bacterial infections can both kill - but testing and treating a patient with clear symptoms of a heart attack for strep doesn't solve the problem.
The same holds true for gerrymandered electoral districts, according to Binghamton University political science researchers. Think of a gerrymander as a form of illness, Associate Professor Daniel B. Magleby explained - a sick map, in effect.
"Understanding and applying the right diagnostic tools allows us to understand what values the map is violating - how it's sick in a particular way," he explained.
Magleby and Professor Michael D. McDonald explore different methods to evaluate possible gerrymanders and their tradeoffs in "Assessing Gerrymandering after the 2020 Census," which recently appeared in Election Law Journal.
The U.S. Constitution requires a census every 10 years to officially count the country's population; at the conclusion of that census, the lines of Congressional districts are redrawn - sometimes in ways that distort the principles of fair elections.
Gerrymandering is an old phenomenon coined by Elbridge Gary in 1812; the term originally referred to the strange shapes imposed on districts to distort electoral outcomes.
However, gerrymandering has been getting more sophisticated and has worsened since the 1950s, McDonald said. While advances and statistical analysis have led to better tools for diagnosing distortions, these same tools can also help execute them.
"We're in a bit of an arms race," Magleby acknowledged.
The values behind fair elections
A 2019 U.S. Supreme Court decision pushed efforts to limit gerrymanders out of the federal courts to the realm of politics and willing state courts. Reformers feared the decision would ultimately make it impossible to police gerrymandering practices.
That hasn't proven to be the case so far.
"Congress, in anticipation of what the Roberts Court was going to do, started to float ideas about how to write rules that would police gerrymandering, McDonald said. "It looks pretty clear that the Republicans don't want to do that, but if the Democrats had a solid majority, they might enact legislation."
In their analysis, McDonald and Magleby applied five methods proposed by scholars to detect gerrymanders to 37 states with three or more congressional districts, using congressional maps enacted after the 2020 census. They found consistent evidence of partisan gerrymandering in four states, consistent evidence of no partisan gerrymandering in 12 states, and mixed evidence in the remaining 21.
A key problem: the methods of analysis target different types of gerrymandering.
"You have to identify the values you want to preserve, and then a diagnostic will follow," McDonald said. "Those values cannot be so vague as 'fairness.'"
State legislatures often play a major role in drawing district lines, which can be problematic in states dominated by a single political party. Nonpartisan or bipartisan redistricting commissions are one answer, but research by McDonald, Magleby and their colleagues shows that such commissions can also result in gerrymanders.
Adding to the complexity: manipulation isn't always negative. Sometimes, district lines must be adjusted to preserve majority rule or to make sure that minority interests are included in the system. Consider New York and Illinois, two states that have a majority of Democratic voters - who tend to cluster in urban areas. If you draw districts based strictly on geography, you will end up excluding the majority of voters from representation based on where they live.
Their solution is to come up with a nuanced rule that indicates when a gerrymander may be in play - something the Supreme Court refused to do. That rule relies on the preservation of two values central to fair elections: that every minority voice should have an opportunity to be heard, and that the majority should rule.
A gerrymander can make it impossible for a minority party to achieve the majority, even if it receives the most votes in an election. Conversely, distorted maps may completely exclude a particular group of people from ever receiving an appropriate amount of representation. While these scenarios may sound the same, they're two different dynamics that require different means of correction.
"Trying to apply the diagnostic for a violation of majority rule to a scenario where we've excluded people, or vice versa, is going to lead to trouble," Magleby said.
Academics often debate the efficacy of particular tools - which has proven counterproductive.
In short, there's no single means to determine whether a map has been manipulated in such a way to create harm. However, tools already exist to determine whether a map violates the principle of majority rule or is drawn to keep a particular group of people from having a voice in the system, the researchers said.
"Gerrymandering will be a threat until we come to the realization that we have to identify the values we want to preserve and then lean on social scientists to construct diagnostics that will tell you when you have and haven't satisfied those values," McDonald said. "We think it's within reach."
