The changes will likely come soonest in the realm of voting rights, where Kennedy has been engaged in an intricate dance at the leading edge of legal arguments. One of the last Court decisions in his final term came in the Gill v. Whitford challenge to potential partisan gerrymanders in Wisconsin’s state legislative maps. In that case, Democratic plaintiffs alleged that GOP-drawn maps created an unlawful partisan advantage, one where Republicans could fail to win the majority of total assembly votes and still capture control of the legislature. The case was anticipated as a potential landmark decision, one in which Kennedy’s career of legal interpretation has been critical.

The Court has never formally ruled on the merits of a challenge of gerrymandering on the basis of political, rather than racial, advantage—indeed, it still hasn’t, since Gill v. Whitford was remanded. Influential conservative minds like Antonin Scalia have been loathe to ever consider potential partisan gerrymanders, since while the Court does establish that politically advantageous maps can be unconstitutional, it has been uncomfortable deciding when that line has been crossed. Kennedy, however, was instrumental in keeping the possibility alive. In his 2004 concurrence in Vieth v. Jubelirer, the outgoing justice essentially put out a call for compelling tests for partisan gerrymanders, keeping hope alive among voting-rights activists that one day they could find an argument that could convince the Court to rule against a partisan gerrymander.

They haven’t convinced the Court yet, and along with its sending Gill v. Whitford back down to lower courts, the Supreme Court has also sent two similar state partisan gerrymandering cases back down to lower courts, instructing plaintiffs to convince the courts of their standing and of concrete violations of individual freedoms by partisan gerrymandering. Kennedy won’t be around for the next round of cases, though, and that’s critical. While the four liberal justices concurred with the conservative justices in a unanimous decision in Whitford, their concurrence essentially created a roadmap for plaintiffs to finally convince courts of the illegality of partisan gerrymandering, including the necessity of arguments that biased maps run afoul of the First Amendment right to freedom of association, and the possible pairing of statewide harms with statewide remedies.

Without Kennedy on board, that roadmap is essentially moot. Whereas the Court’s maneuvering this term set up a cliffhanger on the idea of partisan gerrymandering, the next term was supposed to be the series finale. And the verdict on partisan gerrymandering matters deeply to the near future of political mapmaking.

After the 2013 Shelby County v. Holder decision defanged federal oversight of state elections laws, amid a concerted conservative effort to wrest control of political redistricting and use it to squeeze out as much GOP electoral advantage as possible, federal courts have regularly and relatively easily struck down several racial gerrymanders. But as redistricting has become more sophisticated and as partisanship has become more racially polarized, partisan gerrymandering has emerged as an option for engineering political advantages—even, as Justice Sonia Sotomayor notes, when those advantages are still essentially racial in nature. Indeed, the partisan gerrymandering cases from North Carolina that the Supreme Court recently sent back to lower courts came from jilted Republicans after the Court struck down their original racial gerrymanders created in 2011.