Voter SuppressionGerrymandering

The Impacts of Gerrymandering


Gerrymandering, undoubtedly, has had a significant impact on which party has controlled state legislatures and Congress for centuries. More recently (think 2010), Republicans have done a rather impressive job of using redistricting to their advantage (though both parties generally gerrymander maps in their favor if given the opportunity).

Political advantage in the form of seats is the most obvious effect of gerrymandering, but there are a whole host of other impacts to consider, both in the long term and the short term. We are going to spend some time breaking down how maps, and congress, look when gerrymandering enters the picture.

More Abstract Effects of Gerrymandering

Polarization and Competition

Conventional wisdom suggests that when legislators are given the opportunity to draw their own districts (as is so often the case in states where the state legislature is in charge of redistricting), they will create districts where their own seat is safer. This often means that the seat is less competitive, which many believe results in increased polarization. This is because as districts become more safely red or blue, representatives will have less reason to appeal to voters in other parties and thus will begin to cluster on the outer edges of the spectrum as opposed to the middle. It is a logical conclusion, but does it hold up? Research done by Masket, Winburn, and Wright concluded it did not, at least not in any significant manner. They argued that often when legislatures control redistricting, districts actually become more competitive in an effort for the party in power to win additional seats.

Similarly, the redistricting process has not been found to favor incumbents, according to research done by Stephen Ansolabehere and James Snyder. While intuitively it may seem as if an incumbency advantage could arise from legislatures controlling redistricting, empirical evidence does not support this claim. They find that protecting incumbents is difficult and that an examination of electoral competition (namely the number of competitive districts and the effects of redistricting on the partisanship of incumbents’ districts) reveal little support for the theory of incumbency advantage. Ansolabehere and Snyder are sure to note, however, that legislative redistricting still has its problems. But many of these problems have been tackled since the intervention of the courts in the redistricting process and the mandating of redistricting every ten years.

Majority Minority* Districts

The creation of majority-minority districts have long been an important consideration in the redistricting process. The creation of these districts ensures that large voting blocks cannot be broken up among multiple districts to dilute their political power. Democrats and Republicans have, at various times, each made the case that majority-minority districts could be threatened if partisan gerrymandering were to be eliminated. Section 2 of the Voting Rights Act can, at times, require states to create majority minority districts in order to protect the voting power of minority voters. It has been argued that the creation of these majority-minority districts have often necessitated a partisan gerrymander and if partisan gerrymandering were to disappear, so would these majority-minority districts. However, a report from the Brennan Center dispels this concern and found no connection between partisan bias and majority-minority districts in maps from the 1990s, 2000s, and 2010s. Importantly, the report concludes that banning partisan gerrymandering “can help prevent minority communities from being used to maximize partisan advantage — by either Republicans or Democrats.”

At the other end of the spectrum, there is also concern that Black voters are being concentrated, or packed, into districts to create majority-minority districts that dilute the overall voting power of Black voters because their majority influence is concentrated into  select areas. Such is the worry in Alabama where Democrats believe Black voters have been packed into the 7th district. Majority-minority districts are important for representation, but can be weaponized depending on which party has the advantage.

Majority Minority Districts

At Public Wise, we generally prefer to avoid using the term minority, as it has come to be used as a euphemism to indicate people in the US who are not white, rather than referring to those in the numeric minority in any given situation. In this way, it lumps together groups who do not necessarily have anything in common other than that they are not white. However, much of the discussion around gerrymandering uses this term and so, for the sake of clarity, we use it here to remain consistent with the material we describe and cite.

More Concrete Effects of Gerrymandering

As mentioned in our previous piece, gerrymandering (and redistricting in general) have the power to decide who has control over state legislatures and the House of Representatives. With that knowledge, it is no surprise that there have been huge partisan efforts over the years to control the process.

No one has been more successful in this endeavor than Chris Jankowski, a Republican strategist who in 2010 led REDMAP (Redistricting Majority Project). After major losses in 2008, Republicans were strategizing as to how they could win elections in 2010. Typically, the party not in power has the advantage at the midterms following a presidential election, so Republicans decided to capitalize on that momentum. Broadly, REDMAP’s plan was to win state legislative races in order to gain control of state houses and, by extension, redistricting, and draw congressional maps that favored their candidates. For relatively little financial investment, Republicans were able to draw incredibly precise and gerrymandered maps and sail to power in 2010.

The Democratic response to this has been former Attorney General Eric Holder’s recently created National Democratic Redistricting Committee (NDRC), a redistricting effort that aims to create maps where Democrats can compete. The non-partisan affiliate of NDRC, the National Redistricting Action Fund (NRAF), and it’s grassroots campaign, All On the Line, seek to end partisan gerrymandering by implementing independent, nonpartisan redistricting processes. Although NRAF and AOTL are Public Wise partners, they are newer creations so we are not yet able to fully assess their success in influencing redistricting outcomes.


After all of this, you may be left wondering whether there is a solution to gerrymandering and the problems it creates. The short answer is no, at least not just one.

Independent Redistricting Commissions

Independent redistricting commissions are, on their face, a more appealing and fair method of redistricting. With redistricting no longer controlled by legislators who have quite a bit of skin in the game, it is reasonable to expect that the redistricting process will be less partisan and include less gerrymandering. While the research we discussed earlier delved into issues of polarization, competition, and incumbency advantage, other research suggests that if crafted correctly, independent commissions can mitigate much of the harm of gerrymandering. For example, work from Edwards, Crespin, Williamson, and Palmer found that independent redistricting commissions create significantly more compact congressional districts and split fewer political subdivisions. They note, however, that independent redistricting commissions are still a relatively new phenomenon and that redistricting done after the 2020 census (this current round of redistricting) will provide a better look at their utility.


As mentioned in our last post, technology allows us to create ensembles, or many iterations, of redistricting maps. These maps provide a spectrum of what is possible in the redistricting process. While these maps can be used to assess the quality of a state’s proposal, they can also be used to create quality redistricting plans for a state. Research done by Amariah BeckerMoon DuchinDara Gold, and Sam Hirsch at Tufts University found that an ensemble of maps can be used to consider a variety of factors when redistricting, including the Voting Rights Act and Equal Protection Clause. The authors use Texas as a case study and find that this method of map creation can create better maps for voters, as well as be done in a timely manner when used by the state.

Proportional Representation

Some individuals think the current system of representation, one where voters live in small districts and elect representatives, should be thrown out all together and replaced with a system known as proportional representation. Proportional representation uses multi-member districts, where the proportion of votes a given party receives is how many representatives that party gets in a legislative body. For example, if 40% of votes in a district go to Republicans, then they would receive 40% of that district’s representatives. Many believe that this method of representation will eliminate much of the harmful effects of partisan gerrymandering. Currently, states are required to have the same number of districts as they do representatives in Congress. This law effectively prohibits proportional representation because it does not allow for multi-member congressional districts, a hallmark of proportional representation, so we won’t see what difference it makes in practice anytime soon.

How to Get There

There are two options for redistricting and gerrymandering reform of the current system: national action and state action.

At the national level the law that has the most traction at the moment is the Freedom to Vote Act. The Freedom to Vote Act includes significant redistricting reform, including the banning of partisan gerrymandering and the establishment of neutral standards. While the most recent version of the bill, crafted largely in collaboration with Senator Joe Manchin (D-WV), is a slimmed down version of what was previously introduced by Democrats in HR 1 and the first iteration of the Freedom to Vote Act, the bill would still provide vital guidelines for the redistricting process and cut down on partisan gerrymandering. However the Freedom to Vote Act was recently defeated in the Senate, as it was unable to clear the 60 vote threshold needed to overcome the filibuster and advance the legislation to a final vote. While it is highly unlikely that Democrats will find 10 Republican votes for the Freedom to Vote Act in the near future, parts of the bill could still find their way into other pieces of federal legislation.

At the state level, legislatures can pass laws to reform redistricting procedures by creating clear requirements for the redistricting process and transferring redistricting responsibilities from the state legislature to independent redistricting commissions. So far 8 states use independent redistricting commissions.

While passing a law is one way to accomplish this, it can also be accomplished by ballot measure. Sometimes known as ballot initiatives or popular referendums, ballot measures provide an opportunity for citizens to directly vote on a law rather than the law moving through the state legislature. This occurred in Michigan where citizens led a campaign to put redistricting reform on the ballot for Michiganders to vote on. Ballot measures, however, are not allowed in every state, and efforts are being made in certain states, such as Florida, to limit their use even further.

Redistricting reform to prevent the kind of gerrymandering that occurred in 2010 likely involves both federal and state action and mitigating the effects of gerrymandering will be difficult. But advocating for reform, contacting lawmakers, and making sure your voice is heard at the ballot box are good first steps to ensure that fair maps are drawn that represent voters, not party interests.