30 ALEXANDER v. SOUTH CAROLINA STATE CONFERENCE OF THE NAACP Opinion of the Court D In addition to all this, the District Court also critically erred by failing to draw an adverse inference against the Challengers for not providing a substitute map that shows how the State “could have achieved its legitimate political objectives” in District 1 while producing “significantly greater racial balance.” Cromartie II, 532 U. S., at 258. We have repeatedly observed that an alternative map of this sort can go a long way toward helping plaintiffs disentangle race and politics. In Cooper, we expressed “no doubt that an alternative districting plan . . . can serve as key evidence in a race-versus-politics dispute.” 581 U. S., at 317. By showing that a rational legislature, driven only by its professed mapmaking criteria, could have produced a different map with “greater racial balance,” Cromartie II, 532 U. S., at 258, an alternative map can perform the critical task of distinguishing between racial and political motivations when race and partisanship are closely entwined. For that reason, we have said that when all plaintiffs can muster is “meager direct evidence of a racial gerrymander” “only [an alternative] ma[p] of that kind” can “carry the day.” Cooper, 581 U. S., at 322. Nor is an alternative map difficult to produce. Any expert armed with a computer “can easily churn out redistricting maps that control for any number of specified criteria, including prior voting patterns and political party registration.” Id., at 337 (opinion of ALITO, J.). The Challengers enlisted four experts who could have made these maps at little marginal cost. Dr. Imai’s simulations generated 20,000 different maps—but none that actually controlled for politics. The evidentiary force of an alternative map, coupled with its easy availability, means that trial courts should draw an adverse inference from a plaintiff ’s failure —————— the District Court clearly erred when it found that the Challengers carried their “demanding burden.”