28 RUCHO v. COMMON CAUSE KAGAN, J., dissenting Illicit purpose was simple to show here only because politicians and mapmakers thought their actions could not be attacked in court. See Rucho, 318 F. Supp. 3d, at 808 (quoting Lewis’s statements to that effect). They therefore felt free to openly proclaim their intent to entrench their party in office. See supra, at 4–6. But if the Court today had declared that behavior justiciable, such smoking guns would all but disappear. Even assuming some officials continued to try implementing extreme partisan gerrymanders,5 they would not brag about their efforts. So plaintiffs would have to prove the intent to entrench through circumstantial evidence—essentially showing that no other explanation (no geographic feature or nonpartisan districting objective) could explain the districting plan’s vote dilutive effects. And that would be impossible unless those effects were even more than substantial— unless mapmakers had packed and cracked with abandon in unprecedented ways. As again, they did here. That the two courts below found constitutional violations does not mean their tests were unrigorous; it means that the conduct they confronted was constitutionally appalling—by even the strictest measure, inordinately partisan. The majority, in the end, fails to understand both the plaintiffs’ claims and the decisions below. Everything in today’s opinion assumes that these cases grew out of a “desire for proportional representation” or, more generally phrased, a “fair share of political power.” Ante, at 16, 21. And everything in it assumes that the courts below had to (and did) decide what that fair share would be. But that is —————— 5 A decision of this Court invalidating the North Carolina and Maryland gerrymanders would of course have curbed much of that behavior. In districting cases no less than others, officials respond to what this Court determines the law to sanction. See, e.g., Charles & FuentesRohwer, Judicial Intervention as Judicial Restraint, 132 Harv. L. Rev. 236, 269 (2018) (discussing how the Court’s prohibition of racial gerrymanders affected districting).