In related news, SCOTUS has requested a response from the Texas Attorney General to this lawsuit.
The U.S. Supreme Court has told Texas Attorney General Greg Abbott to respond by June 28 to Democratic claims that the Republican-dominated Legislature had no compelling governmental reason to redraw congressional lines last year.
It was unclear Tuesday whether the request indicates that the Supreme Court might hear arguments in the Texas redistricting appeals.
Abbott initially did not file a response to the Democrats' request to argue before the Supreme Court. On Friday, the clerk of the court sent Abbott's solicitor general, Ted Cruz, a letter asking Texas to tell the court why it should not hear the cases.
The Seventh Edition of Supreme Court Practice, a handbook for lawyers taking cases before the court, says responses such as that asked of Cruz are seldom necessary. The court will ask for one if it thinks the party asking to be heard "may have some merit," and the court wants the other party to explain why it does not, the handbook says.
A three-judge federal panel ruled in January that congressional lines produced after three special sessions in Austin would stand. Lawyers representing five sets of Texas plaintiffs appealed that ruling to the high court, which has yet to decide whether it will hear the Texas cases.
Of five Democratic lawsuits challenging the new lines, four relied heavily on arguments that the new lines diluted minority voting strength. But one lawsuit filed by three East Texans directly challenged lawmakers' authority to take up redistricting outside the once-a-decade format.
That mid-decade question is similar to a Colorado case the court also might hear.
The Supreme Court has rescheduled discussion of whether to hear the Colorado case at least four times. That lawsuit turns on whether the Colorado Constitution stands up to U.S. Constitutional muster in forbidding mid-decade redistricting.
The court's latest decision to reschedule that discussion was Thursday, the day before its clerk sent the letter to Texas.
In a Pennsylvania case decided by the high court earlier this year, most judges agreed that purely partisan justification for redrawing lines doesn't meet the constitutional requirement that there be a legitimate governmental purpose for mid-decade redistricting.
They let that state's GOP-driven lines stand, though, with four justices saying a clear line could never be drawn separating decisions meant to favor one party from those that incidentally favor that party. A fifth judge in the 5-4 decision also noted that Pennsylvania, unlike Texas, did not have any lines in place other than the ones drawn after the 1990 census.