Thomas, J., dissenting
would not yield a race-neutral case for treating the plaintiffs’ approach as a suitable benchmark: Absent core retention, there is no apparent race-neutral reason to insist that District 7 remain a majority-black district uniting Birmingham’s majority-black neighborhoods with majority-black rural areas in the Black Belt.
Finally, it is surely probative that over 2 million race-neutral simulations did not yield a single plan with two majority-black districts, and even 20,000 simulations with a one-majority-black-district floor did not yield a second district with a black voting-age population over 40%. If any plan with two majority-black districts would be an “out-out-out-outlier” within the likely universe of race-neutral districting plans, Rucho, 588 U. S., at ___ (Kagan, J., dissenting) (slip op., at 19), it is hard to see how the mere possibility of drawing two majority-black districts could show that a one-district map diluted black Alabamians’ votes relative to any appropriate benchmark.[1]
- ↑ The majority points to limitations of Dr. Duchin’s and Dr. Imai’s algorithms that do not undermine the strong inference from their results to the conclusion that no two-majority-black-district plan could be an appropriate proxy for the undiluted benchmark. Ante, at 26, 28–29. I have already explained why the fact that Dr. Duchin’s study used 2010 census data is irrelevant. See n. 9, supra. As for the algorithms’ inability to incorporate all possible districting considerations, the absence of additional constraints cannot explain their failure to produce any maps hitting the plaintiffs’ preferred racial target. Next, while it is true that the number of possible districting plans is extremely large, that does not mean it is impossible to generate a statistically significant sample. Here, for instance, Dr. Imai explained that “10,000 simulated plans” was sufficient to “yield statistically precise conclusions” and that any higher number would “not materially affect” the results. Supp. App. 60. Finally, the majority notes Dr. Duchin’s testimony that her “exploratory algorithms” found “thousands” of possible two-majority-black-district maps. 2 App. 622; see ante, at 27, n. 7. Setting aside that Dr. Duchin never provided the denominator of which those “thousands” were the numerator, it is no wonder that the algorithms in question generated such maps; as Dr.
