And she may well be there for months to come, a fact that has implications both for the court and for the 75-year-old justice, who commented ruefully to an audience of West Point cadets a week ago that "I did my best to retire from the Supreme Court this summer."
Recalling the Labor Day telephone call from President Bush, informing her that he was redesignating John G. Roberts Jr., her intended successor, for the position of chief justice, Justice O'Connor told the cadets, "They say your country calls sometimes, but I didn't know they meant it called on the telephone!"
Justice O'Connor's continued tenure on the court, which is now likely to stretch into the new year, means that she will participate in the initial stage of many more cases than had at first appeared likely.
If she sits through Dec. 7, the court's last argument day before a four-week holiday recess, she will have heard arguments in 31 cases. These include the Oregon assisted-suicide case that was argued Oct. 5, as well as an abortion case from New Hampshire that raises an important procedural issue, to be argued on Nov. 30.
While she will cast a post-argument vote in all the cases she hears, along with the other justices, her vote will count in the end only if she is still on the court when the decision is issued. If she is gone by then, the decision will be issued without her.
In the event of a 4-to-4 tie, not unlikely given Justice O'Connor's position in the middle of the court, the remaining justices will decide whether to schedule a new argument or to announce the tie, a disposition that affirms the lower court's opinion without setting a precedent for future cases.
It is evident from her active participation during the new term's argument sessions that she is doing her homework.
More than that, she has maintained a busy off-the-bench schedule. She went on network television to promote her newly published autobiographical children's book. She has agreed to serve as grand marshal for the Rose Bowl parade on Jan 2. She is organizing a conference on the state and future of the legal profession.
Despite her thwarted plans and her ailing husband, Justice O'Connor projects not the stress that many people might experience in such circumstances, but energy and good humor. Further, it is obvious that she does not intend to fade quietly from the scene.
At West Point last Thursday to accept the military academy's Thayer Award, her brief remarks were far from the civic bromides that public figures, including Supreme Court justices, often turn to on such occasions.
Instead, she presented a pointed and timely critique of the failure by both the White House and Congress to set clear rules for the treatment of detainees.
"What law governs the detention and interrogation of terrorist suspects?" the justice asked the future military officers. "And how are you to know what standards apply?"
Playing off the West Point motto of "Duty, Honor, Country," she continued, according to the text made available by the court: "What does your duty demand? What does your honor demand? And what does your country demand? It is hard enough to answer the first two questions, but harder still when the nation's elected leaders are silent about the last."
She referred to two cases the court decided in June 2004, one rejecting the Bush administration's position that the federal courts had no jurisdiction over conditions for detainees at Guantánamo Bay, Cuba, and the other, in which she wrote the controlling opinion, insisting that United States citizens had a "meaningful opportunity" to challenge the basis for their detention.
These were "modest" and "limited" decisions, she said, adding: "This is where we expect Congress to step in. But it has done surprisingly little to date to clarify United States policy towards prisoners in the war on terror." She said, "I think it is not too much to say that I believe some clarity from Congress and the president would be welcomed by our armed forces."
These were such unusual remarks for a sitting justice as to raise the question of whether Justice O'Connor, in the oddly prolonged twilight of her tenure, might now be feeling liberated from convention and free to speak her mind. If so, the country may come to know Sandra O'Connor better in the coming months than in the past 24 years.