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The Supreme Court Takes on Partisan Gerrymandering: Five Things You Need to Know

The Supreme Court is set to rule on a major partisan gerrymandering case that could set a national standard for how legislative maps are drawn.

June 7, 2018

This month, the Supreme Court will announce its decisions in a pair of major partisan-gerrymandering cases, Gill v. Whitford (from Wisconsin) and Benisek v. Lamone (from Maryland). The rulings could be the first by the Supreme Court to put meaningful limits on politicians’ ability to draw election districts for their partisan advantage.

And not a minute too soon. Extreme gerrymandering reached unprecedented heights this decade, enabled by sophisticated new technology and increasingly robust data about voters. If the Court doesn’t step in, the next set of maps drawn in 2021 could be even worse for voters.

Here are a few key things to get you up to speed with the cases and their stakes: 

1. What happened in Wisconsin and Maryland?

Voters in Wisconsin and Maryland are suing to dismantle extreme gerrymanders created by politicians who dominated the 2011 round of redistricting.

In Wisconsin, voters are challenging their state assembly map, which Republicans gerrymandered in extreme fashion. The gerrymander secured Republicans a sizable majority that has been insulated from shifts in voter preferences ever since: In 2012, Republicans won 60 of the 99 seats in the General Assembly despite winning only 48.6 percent of the two-party statewide vote; in 2014, they won 63 seats with only 52 percent of the statewide vote. When a panel of three judges struck down the plan as an “aggressive partisan gerrymander,” it was the first time in American history that a federal court declared a map unconstitutional on these grounds. Wisconsin officials then appealed to the Supreme Court. A ruling in favor of the Wisconsin voters would force a redrawing of the state assembly map, although most likely for the 2020, rather than the 2018, election.

Meanwhile, Maryland voters challenged their state’s congressional map, a Democratic gerrymander that involved shifting hundreds of thousands of voters among districts — including moving large numbers of voters from rural Maryland out of the 6th Congressional District and replacing them with voters from suburban Washington, D.C. These manipulations of the district lines converted a map that more fairly represented Democrats and Republicans into one that gives seven of the state’s eight congressional seats to Democrats in each election. After the lower court declined to block use of the map for the 2018 elections, Maryland voters appealed to the Supreme Court.

2. How does extreme gerrymandering hurt American democracy?

The extreme partisan gerrymanders this decade in Wisconsin, Maryland, and a handful of other states are harmful to voters because they effectively predetermine election results, making it nearly impossible for parties to win more seats even if they win significantly more votes.

At the national level, Brennan Center reports have found that Republican gerrymandering accounts for at least 16 to 17 GOP seats in the current Congress, and that thanks to gerrymandering, Democrats may have to win the national popular vote by more than 10 1/2 points to win back the House in 2018.

But gerrymanders don’t just hurt voters from the political party that’s on the outs during the redistricting process. They also can undercut the political power of communities of color. Take Maryland. There, Democrats spread African-American voters — their most reliable supporters — out among the districts to shore up a 7-to-1 majority, rejecting a map that would have given greater political voice to African Americans but that would have given Democrats only a 5-to-3 edge.

And these problems could get worse soon.

Since the 2011 redistricting, mapping programs and computers have become more powerful, and politicians have stockpiled more detailed voter data, making it easier for would-be gerrymanderers to create even more durably biased maps. Both political parties — and allied groups fueled by anonymous dark money — are already gearing up to battle for state legislatures, with an eye to gerrymandering their states’ maps in 2021.

3. What issue do these cases ask the Court to decide?

The Supreme Court has already ruled that extreme partisan gerrymandering violates the Constitution. Even Justice Antonin Scalia agreed that “excessive injection of politics [in redistricting] is unlawful.” The problem is that the Court hasn’t articulated a standard for identifying when a gerrymander crosses the line into unlawful territory.

Whitford and Benisek ask the Court to establish that standard, which lower courts can then use to identify when a map goes too far: words that everyone can relate to, like “it’s wrong and unconstitutional for legislators to lock their party into power.” Or as Justice Anthony Kennedy suggested during the Whitford argument, it’s wrong and unconstitutional to manipulate the redistricting process “to favor party X or party Y.”

Importantly, for all the talk in some circles about math “saving democracy,” these cases don’t require the Court to get into the nitty-gritty of math or statistics. While mathematical or statistical evidence can help judges identify bad maps, it’s just evidence, not a legal principle. Whitford and Benisek are about commitments to electoral fairness, representation, and accountability that come straight out of our Constitution.

4. Could the Court decide the cases without deciding the big issue?

It’s possible. Wisconsin, for example, has argued the Court should dismiss Whitford by ruling that voters can’t challenge a state’s map as a whole, but can only challenge the specific districts where they live. Likewise, at the oral argument in Benisek, several Justices suggested that the Court could simply decide that the plaintiffs haven’t satisfied all of the legal requirements to get Maryland’s map blocked before trial.

But even if the Court does rule without reaching the big question, that won’t be the end of partisan-gerrymandering cases at the Supreme Court. In fact, a case from North Carolina could give the Supreme Court another chance to decide the issue as early as next term.

5. How would rulings in these cases affect voters?

A ruling for the plaintiffs in one or both cases could put important limits on extreme partisan redistricting. Such a ruling won’t fix all the problems with our redistricting processes and likely wouldn’t impact the 2018 midterms, but it would set the stage for fairer maps in 2020 and beyond.

On the other hand, a loss for the plaintiffs (or a punt by the Supreme Court) would raise the urgency of reform efforts in the states. Independent redistricting commissions in California and Arizona have shown that reforms work, producing maps that are measurably more responsive to voter preferences. And, around the country, reform efforts are gaining traction. By a 3-to-1 margin, Ohio voters recently passed a strong constitutional amendment to reform the way congressional redistricting is done. Additional reform measures are likely to be on the ballot in Michigan, Colorado, Utah, and Missouri this fall, as well.

Congress also could use its powers under the Elections Clause to pass legislation to improve the processes for drawing congressional districts. Federal legislation could range from strengthening the rules around congressional redistricting to requiring all states to use independent commissions for drawing congressional lines.


This post is part of the Brennan Center’s work to Protect the Vote in the 2018 midterm elections.

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