[yttribium]

Gerrymandering is required by federal law to make sure that blacks are able to elect black representatives; this has obvious second order effects in how the rest of the map is drawn under adversarial conditions. Somehow it seems unlikely that this requirement is going away anytime soon, so any proposed mechanism that does not accommodate this constraint is going to be impractical.

[alwa]

Fortunately, the authors consider this and address it in part 4.2. They propose drawing and freezing-in-place the VRA-mandated majority-minority districts as a first step, before applying their technique to the rest of the districts. They test that approach and find that doing it that way still buys you approximately the same degree of neutrality on the overall map, relative to the status quo.