Gerrymandering of voting districts (arranging the district boundaries to try and give a partisan advantage) is a result of a two party system. Basically it boils down to: “to the victor go the spoils”.

The Supreme Court ruled that defining voting districts is fundamentally a political issue. The Constitution vests power in state legislatures to draw their own lines and to set the rules of line drawing; protected by the tenth amendment.

Federal judges have no license to reallocate political power between the two major political parties, with no plausible grant of authority in the Constitution, and no legal standards to limit and direct their decisions. “[J]udicial action must be governed by standard, by rule,” and must be “principled, rational, and based upon reasoned distinctions” found in the Constitution or laws. Vieth, 541 U. S., at 278, 279 (plurality opinion). Judicial review of partisan gerrymandering does not meet those basic requirements.

As the left has become more dominate at the Federal level, voters have responded by making state legislatures and governorships more Republican. In an attempt to counter this trend, the left has spent millions of dollars in efforts to gave federal courts the power to erode decisions made by Republican state legislatures.

This is a sweeping rejection well beyond what would have occurred with a substantive evaluation of partisan gerrymandering. There will be no wiggle room for district court judges to try to get involved somehow. For better or worse, partisan gerrymandering is subject to the partisan political process, not the sometimes seemingly partisan judicial process.

Source: https://legalinsurrection.com/2019/06/supreme-court-rejects-challenges-to-partisan-gerrymandering/