26 RUCHO v. COMMON CAUSE KAGAN, J., dissenting any measure, a map that produces a greater partisan skew than any of 3,000 randomly generated maps (all with the State’s political geography and districting criteria built in) reflects “too much” partisanship. Think about what I just said: The absolute worst of 3,001 possible maps. The only one that could produce a 10–3 partisan split even as Republicans got a bare majority of the statewide vote. And again: How much is too much? This much is too much: A map that without any evident non-partisan districting reason (to the contrary) shifted the composition of a district from 47% Republicans and 36% Democrats to 33% Republicans and 42% Democrats. A map that in 2011 was responsible for the largest partisan swing of a congressional district in the country. See Lamone, 348 F. Supp. 3d, at 519. Even the majority acknowledges that “[t]hese cases involve blatant examples of partisanship driving districting decisions.” Ante, at 27. If the majority had done nothing else, it could have set the line here. How much is too much? At the least, any gerrymanders as bad as these. And if the majority thought that approach too casespecific, see ante, at 28, it could have used the lower courts’ general standard—focusing on “predominant” purpose and “substantial” effects—without fear of indeterminacy. I do not take even the majority to claim that courts are incapable of investigating whether legislators mainly intended to seek partisan advantage. See ante, at 19–20 (focusing on the difficulty of measuring effects). That is for good reason. Although purpose inquiries carry certain hazards (which courts must attend to), they are a common form of analysis in constitutional cases. See, e.g., Miller v. Johnson, 515 U. S. 900, 916 (1995); Church of Lukumi Babalu Aye, Inc. v. Hialeah, 508 U. S. 520, 533 (1993); Washington v. Davis, 426 U. S. 229, 239 (1976). Those inquiries would be no harder here than in other contexts.