The South Carolina GOP is trying a tactic of just not drawing a new map, the result of which will either be that the old 2010 map stays in place, or if they are forced to draw a map at the last moment, they can draw a map that won’t pass judicial muster but late enough that the courts will decide to keep the illegal map in place.
The population in SC has shifted to the point where it’s likely that Democratic-leaning urban areas have grown significantly in population, so rather than the normal gerrymandering, there would straight up be districts with something like twice as many people as other ones, and as a result the people in those districts would get half a vote in the relevant elections.
South Carolina Republicans are doing this deliberately to test the Supreme Court’s dedication to upholding the principle that legislative district must be roughly equal in population as found in Reynolds v. Sims and Wesberry v. Sanders. For all the chicanery that Republicans are able to pull off with gerrymandering, they cannot escape the fundamental demographic reality that the population in blue urban areas is growing and in red rural areas is shrinking. They are already approaching the limit of what gerrymandering can do to stave off this reality – IF they’re required to gerrymander district of equal populations.
But if they can create “rotten boroughs” by letting depopulating rural areas keep their same number of districts even as swelling urban areas are held to the same number they have, they can keep the balance of power in their favor regardless of demographic changes. And it’s not unthinkable that the Supreme Court would be amenable. Thomas and Alito have expressed skepticism about “one person, one vote.” Gorsuch would almost certainly be on board. Roberts and Kavanaugh both held in Rucho v. Common Cause that partisan gerrymandering was nonjusticiable (admittedly, not the same question). Who know how Barrett would find?
I would think that whether states can gerrymander legislative districts to achieve partisan outcomes, and whether the federal government can impose standards on how states redistrict, are fundamentally different questions. I have a hard time seeing this Supreme Court deciding that the later is nonjusticiable.
Gerrymandering based on putting likely party voters in one side of a line or other is nonjusticiable as a matter of U.S. Supreme Court jurisprudence. (State supreme courts are another matter.) But failing to create districts of equal population has always been justifiable, at least so far.
And of course, the rationale for it not being justiceable is that it’s a political question: That is to say, if you don’t like being denied a vote, then the solution is to vote out the people who are denying you a vote.