Sandra Day O’Connor, who retired from the Supreme Court seven years ago, made some news the other day. In an interview with the editorial board of the Chicago Tribune, she expressed misgivings about one of the signature decisions of her judicial career: Bush v. Gore. “Maybe the Court should have said, ‘We’re not going to take it, goodbye.’ ” The case, she said, which effectively awarded the 2000 Presidential election to George W. Bush, “stirred up the public” and “gave the Court a less than perfect reputation.”

It was not a full-fledged denunciation of the Court’s opinion, but it was a decided shift in O’Connor’s views. Ever since the decision in 2000, in which a five-Justice majority ended a recount of votes that had been ordered by the Florida Supreme Court, O’Connor has defended the result publicly. (She did so on “The Daily Show.”) I have heard O’Connor defend Bush v. Gore any number of times, at events ranging from law-school convocations to small dinner parties.

So what changed? The Republican Party—O’Connor’s Republican Party.

The Court, in its history, has had many Justices who formerly held elective office—Earl Warren, a former Governor of California; William Howard Taft, who’d been President; Hugo Black, a onetime Senator—but O’Connor was last to have done so. (She was a state senator in Arizona.) That experience has always been crucial to understanding her judicial philosophy. Temperamentally as well as politically, she was a Republican, to be sure, but she was a moderate conservative; even more than Ronald Reagan, the President who appointed her, George H. W. Bush was O’Connor’s ideal President. In the ballot box as well as on the Supreme Court, O’Connor voted for George W. Bush thinking that he would be a President much like his father. (The story of O’Connor’s election-night rooting for Bush in 2000 is well-known; I’ve told it in two books.)

As for the Presidency of the younger Bush, O’Connor was disappointed, to put it mildly. The story of the last decade or so of her life is the story of her increasing alienation from the modern Republican Party. The key moment for her was the Terri Schiavo case, in 2005, when the President and congressional Republicans mobilized overnight to intervene in the case of a Florida woman who was in a persistent vegetative state, and attempted to overrule her husband’s request to remove her feeding tubes. O’Connor, who was at that moment dealing with the descent of her own husband into Alzheimer’s disease, was appalled at the fanaticism on display. But largely because of her husband’s condition, O’Connor nevertheless announced her departure from the Court later that year—and gave George W. Bush the chance to put his stamp, and that of the modern Republican Party, on her beloved Court.

In the past seven years, O’Connor has been increasingly clear about her disenchantment with the work of her successors, especially Chief Justice John G. Roberts and Samuel A. Alito, Jr., (who took her seat). She has been harshly critical of the Court’s decision in Citizens United, which revolutionized the law of campaign finance. Indeed, her major outside activity since retiring has been to try to persuade states to have a system of appointed, as opposed to elected, judges. A primary reason why O’Connor opposes judicial election is because of the influence of campaign contributions—which is, of course, precisely the kind of spending allowed by Citizens United.

It may be that O’Connor chose this moment to speak out because she knows (or suspects) that the Court is about to demolish one of her most important achievements. In 2003, O’Connor wrote the majority opinion in Grutter v. Bollinger, which allowed the use of affirmative action in admissions in higher education. The decision was a classic O’Connor compromise: she supported diversity but not quotas; she embraced racial preferences but put a time limit on their use—twenty-five years. But now, just a decade later, the Court appears poised to undo, or at least limit, O’Connor’s decision. In the next month or so, the Justices will decide Fisher v. University of Texas, which is a direct challenge to Grutter. The prospect of a thwarted legacy focusses any retired Justice’s mind.

And O’Connor was not alone as a Republican Justice looking on with horror at what her party has become. The two Justices who left the Court after O’Connor were also Republicans who departed aghast at the modern Republican Party. David Souter and John Paul Stevens were so repulsed by the party of George W. Bush that they gave the most precious gift any Justice can proffer to his successor, Barack Obama—their seats on the Court. There is no more eloquent testimony to the evolution of the Republican Party than the ideological fate of the last three Justices to leave the Supreme Court: O’Connor, Souter, and Stevens. In this way, O’Connor’s apostasy on Bush v. Gore is a surprise—but perhaps only because it took so long.

Photograph by Bill Clark/CQ Roll Call/Getty.