The Supreme Court of the United States has held that unless there is adequate justification, a federal court-ordered plan for reapportionment of a state legislature must avoid use of multimember districts and achieve population equality with only de minimis variation.
Chapman v. Meier, 420 U.S. 1 (1975).
David R. Johnson,
Federal Courts - Supervisory Power - Court-Ordered Legislative Apportionment,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol14/iss3/9