32 COOPER v. HARRIS Opinion of the Court in the assignment of voters to an earlier incarnation of District 12. See 532 U. S., at 241; supra, at 5. And as the State emphasizes, a part of our opinion faulted the Cromartie plaintiffs for failing to offer a convincing account of how the legislature could have accomplished its political goals other than through the map it chose. See 532 U. S., at 257–258. We there stated: “In a case such as this one where majority-minority districts . . . are at issue and where racial identification correlates highly with political affiliation, the party attacking the legislatively drawn boundaries must show at the least that the legislature could have achieved its legitimate political objectives in alternative ways that are comparably consistent with traditional districting principles. That party must also show that those districting alternatives would have brought about significantly greater racial balance.” Id., at 258. According to North Carolina, that passage alone settles this case, because it makes an alternative map “essential” to a finding that District 12 (a majority-minority district in which race and partisanship are correlated) was a racial gerrymander. Reply Brief 11. Once again, the dissent says the same. See post, at 7. But the reasoning of Cromartie II belies that reading. The Court’s opinion nowhere attempts to explicate or justify the categorical rule that the State claims to find there. (Certainly the dissent’s current defense of that rule, see post, at 8–11, was nowhere in evidence.) And given the strangeness of that rule—which would treat a mere form of evidence as the very substance of a constitutional claim, see supra, at 29–31—we cannot think that the Court adopted it without any explanation. Still more, the entire thrust of the Cromartie II opinion runs counter to an inflexible counter-map requirement. If the Court