The U.S. Supreme Court’s Wisconsin gerrymandering decision on Monday showed the fight for Justice Anthony Kennedy’s vote continues more than a decade after the justices last considered the lawfulness of excessive partisanship in redistricting maps.

Chief Justice John Roberts Jr., writing for a unanimous court in the case, Gill v. Whitford, stressed that the court was deciding only one threshold question: What must challengers to partisan gerrymanders prove to show they have standing to raise their claims? A second question—which the court did not reach—focused on whether the courts even have the authority to resolve the claims.