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Five Takeaways from North Carolina’s Groundbreaking Partisan Gerrymandering Decision

The legal wave builds: a landmark ruling offers key insights for understanding and deciding partisan gerrymandering claims

January 16, 2018

Last week, a panel of three federal judges struck a power­ful blow against partisan gerry­man­der­ing with a land­mark opin­ion that declared North Caro­lin­a’s egre­giously gerry­mandered congres­sional map uncon­sti­tu­tional.

Although a lot of the initial buzz around the opin­ion by Fourth Circuit Judge James A. Wynn has centered on the prospect of North Caro­lin­a’s map being redrawn, the opin­ion is strik­ing in another regard: It makes many of the thorn­i­est and most hotly contested issues in these cases seem, well, pretty simple.

In fact, while the Supreme Court has long wondered whether courts could easily handle partisan-gerry­man­der­ing claims, the North Caro­lina panel’s decision shows that these claims are not only manage­able, but also similar to the types of things courts have done for decades in a vari­ety of other cases.

The opin­ion’s two-hundred-plus pages are packed with insights, but here are five big takeaways:

1.   Social Science is Just Evid­ence

Social science has come to play an import­ant role in partisan-gerry­man­der­ing cases, but its import­ance is frequently over­em­phas­ized or misun­der­stood.

The panel’s opin­ion cuts through the confu­sion, offer­ing a simple way to under­stand the role of social science by distin­guish­ing between “stand­ards” and “evid­ence,” and putting social science in the “evid­ence” basket.

Stand­ards, as the panel explains, are the legal prin­ciples that courts are trying to uphold when they rule a map uncon­sti­tu­tional. Stand­ards include prin­ciples like “the govern­ment [should] act impar­tially,” it should “not infringe on the right to vote,” or it should “not burden indi­vidu­als based on the exer­cise of their rights to polit­ical speech.”

Evid­ence consists of facts—pieces of inform­a­tion—that help courts identify when a stand­ard has been viol­ated. In the North Caro­lina case, there’s a lot of evid­ence. Take, for example, legis­lat­ors’ on-the-record state­ments about their intent to create a map that would reli­ably give Repub­lic­ans ten congres­sional seats and Demo­crats three. And elect­oral returns show­ing that they succeeded.

Social science is another import­ant type of evid­ence, which can help confirm what other evid­ence seems to show. Partisan-symmetry meas­ure­ments (like the effi­ciency gap or mean-median differ­ence) show that North Caro­lin­a’s map produces 10-to-3 congres­sional deleg­a­tions because it makes it system­ic­ally harder for Demo­cratic voters to win elec­tions. Large collec­tions of simu­lated maps show that Demo­cratic voters’ disad­vant­ages in winning elec­tions are the result of the mapmakers’ inten­tional choices.

Even Supreme Court Justices and exper­i­enced comment­at­ors often miss this stand­ard-versus-evid­ence distinc­tion. In the process, they fall into a common trap of assum­ing that plaintiffs in partisan-gerry­man­der­ing cases are asking the Court to “consti­tu­tion­al­ize social science.” Really, plaintiffs are just asking the Court to provide a stand­ard. And, in exchange, they’re offer­ing evid­ence (includ­ing social-science evid­ence) that courts can use to figure out whether the stand­ard’s been viol­ated.

Others have writ­ten about how the North Caro­lina has vindic­ated the social science for meas­ur­ing gerry­manders. The decision has done that. But perhaps its greater import is that it situ­ates the social science in the proper context: Social science is evid­ence and just that.

In the end, a map isn’t uncon­sti­tu­tional because a social-science metric gives a map a score of X percent or Y percent. The map’s uncon­sti­tu­tional because it treats voters unfairly, and the metric—along with a lot of other evid­ence—helps the Court see that there’s some unfair­ness inten­tion­ally baked into the map.

2.    Courts Use Social-Science Evid­ence All the Time

The panel also points out that the use of social science to help solve legal prob­lems is noth­ing new in Amer­ican consti­tu­tional law. In fact, abso­lutely found­a­tional Supreme Court opin­ions are based on it.

While some of the evid­ence on which the Court has previ­ously relied is simple “descript­ive stat­ist­ics,” some of it is more complic­ated. For example, the Court has used advanced tech­niques to meas­ure racially polar­ized voting in cases brought under the Voting Rights Act, to identify viol­a­tions of anti­trust law, and to reshape courtroom proced­ures.

Given all this, the unique­ness of partisan-gerry­man­der­ing claims does­n’t come from their use of math, stat­ist­ics, and other meth­ods developed in the academy. Instead, it comes from the strange unwill­ing­ness of courts to use those meth­ods to solve gerry­man­der­ing when they’ve embraced them for so many other import­ant prob­lems.

3.    Gerry­man­der­ers Use Social Science, Too

Sneaky map-draw­ers who have been caught red-handed frequently claim that it’s impossible to gerry­mander­—that is, reli­ably game a map in favor of one party—be­cause it’s impossible to predict how voters will vote. Simil­arly, when faced with social-science evid­ence that shows how elec­tions would turn out differ­ently if district lines were drawn differ­ently, they argue that every elec­tion is unique. In two simple moves, the panel dismantles these defenses.

First, the panel shows how experts can predict outcomes simply by compar­ing how precincts voted across multiple elec­tions involving differ­ent candid­ates and differ­ent seats.

Second—and not without a touch of irony—the court high­lights the words and deeds of the defend­ants and their own experts:

As with much of the evid­ence in this case, a plaintiff’s attor­ney could not have scrip­ted it any better.

Crucially, however, this beha­vior isn’t unique to North Caro­lina. As we’ve seen in other recent cases where plaintiffs were able to get discov­ery—such as Wiscon­sin, Mary­land, and Pennsylvania—legis­lat­ors and their consult­ants have gerry­man­der­ing down to a science that’s only going to get more precise and damaging as time goes on.

When mapmakers are draw­ing lines, they’re not making guesses based on some earthy and impre­cise folk wisdom. Instead, they’re rely­ing on increas­ingly abund­ant data about how voters actu­ally vote, data that’s frequently conver­ted into indexes that can be used to predict, very accur­ately, how specific precincts will perform in many differ­ent scen­arios. How else could mapmakers justify the fees they charge for their “services”?

4.   The Courts Need to Catch Up with the Social Science

For decades, federal judges have debated whether the judi­ciary could risk getting involved in partisan-gerry­man­der­ing disputes. When the Supreme Court last took up the issue in the mid-2000s, a major­ity of Justices seemed to think it was better to stay out. As the panel explains, however, times have changed and the calcu­la­tion has flipped.

Novelty, the panel contin­ues, is no longer an excuse for inac­tion. 

With force­ful argu­ments like this, the panel isn’t simply resolv­ing a dispute between the parties. It’s provid­ing an extens­ive and pretty color­ful account of the federal courts’ role and respons­ib­il­it­ies, one that speaks directly to the Supreme Court’s hesit­a­tions.

5.   Partisan-Gerry­man­der­ing Claims can be Manage­able and Predict­able

The panel’s last major contri­bu­tion isn’t any single passage, but rather, the sum total of what its opin­ion demon­strates: While the Supreme Court has been hesit­at­ing—with some members of the Court even call­ing the social science “gobbledy­gook” and compar­ing proofs for partisan-gerry­man­der­ing claims to recipes for steak rub—the district courts have been moving ahead, respons­ibly and sure-footedly.

The North Caro­lina case marks the second time in a little over a year that a court has been able to convert the kinds of argu­ments and evid­ence presen­ted by the plaintiffs here into a coher­ent ruling against partisan gerry­man­der­ing. (The panel opin­ion in the Wiscon­sin gerry­man­der­ing case, Gill v. Whit­ford, is the first.) The authors of these opin­ions include both Demo­cratic and Repub­lican appointees, who—while undoubtedly exper­i­enced and capable—ar­en’t social-science experts. Using these opin­ions as guides, it would be easy to handi­cap the like­li­hood of a map being struck down and to explain why a map crossed a consti­tu­tional line.

So, in the face of any linger­ing concerns that partisan-gerry­man­der­ing claims are too hard for the courts to handle: Proof’s in the pudding.

Or the steak rub. 

(Photo: Think­stock)