Well, no. It turns out that the Supreme Court has never exactly settled that question. SCOTUS has found that gerrymandering violates equal representation only when it is done on the basis of race. It seems that doing it to favor Republicans -- or Democrats -- is pretty much OK.
Or, put another way, if you can convince the courts that you're just being political, you can get away with packing the district racially. Actually that was exactly what the justices were struggling with in Monday's hearings of two cases where the two factors seem to be entangled. As described by the New York Times' Adam Liptak:
"The two cases, from Virginia and North Carolina, were the court’s latest attempts to solve a constitutional puzzle: how to disentangle the roles of race and partisanship when black voters overwhelmingly favor Democrats. The difference matters because the Supreme Court has said that only racial gerrymandering is constitutionally suspect."
Justice Elena Kagan summarized the dilemma: “'If it’s politics, it’s fine. If it’s race, it’s not.” The problem is that “race and politics correlate.” And therefore attorney Paul Clement, representing both states, pointed out that it is very easy to ascribe racial motive when it was in fact "permissible partisan behavior."' And I would add: vice versa. It is very easy to call it political when it's really racial.
The reality of voting patterns today makes it obvious that the simplest way to increase the Democratic votes in a district (legal) is to redraw the lines so that more African-American residential areas are included (which would be illegal). And vice versa.
Liptak pointed out that it's even more complex than considering motivation. In the Virginia case, the suit was brought by voters who claimed that lines drawn after the 2010 census had actually decreased their number of voters. Apparently, the previous district lines had given them more than 55%. This then violated the Voting Rights Act, "which forbade the diminishment of minority voters' ability to elect candidates of their choice."
The North Carolina case also involved conflicting rulings based on what criteria are used for judging whether race was the main factor. Justice Breyer saw the difficulty as rooted in historical wrongs making it close to insoluble. As he tried to explain: “There were many states that had many black citizens and had no black representation. . . . And the problem is, how does the law permit the creation of that, and at the same time, prevent the kind of packing that might appear in other cases, which is gerrymandering? No one, I think, has a good answer to that question. There is just slightly better, slightly worse.”
Here we have another example of a basic question in constitutional law begging to be resolved; and a political power grab by Republicans means the Supreme Court is not operating at full strength. What happens if they end up in a 4 to 4 tie? Well, we know the legal answer. The lower court decision will stand -- until another case comes along when the court has been reconstituted. Decisions of 4 to 4 are not considered precedent-setting.
What I don't understand -- and don't like -- is why it is permissible to stack the deck for any reason based on which party is in power at the time? District voting lines should be drawn by an impartial, independent board -- as a few states have chosen to do. That should be the standard method mandated by federal law, in my opinion.