The high court said it was unclear whether the judges in Texas followed the appropriate standards and sent the cases back for further proceedings.
At issue were the maps that Texas will use in its primary contests set for April 3 that will decide party candidates for congressional and state legislature elections in November.
The dispute had been closely watched because it could help decide whether Republicans or Democrats gain as many as four seats in the U.S. House of Representatives in November.
Texas Republican officials appealed to the Supreme Court, said the lower-court overstepped its authority and argued the judges should have deferred to the maps drawn by the elected lawmakers. Those maps favor Republican candidates.
The officials won at least a partial victory, though the court stopped short of adopting the maps drawn by the Republican-dominated legislature.