Chief Justice Earl Warren tried to time his retirement so President Lyndon B. Johnson could appoint his successor before the 1968 election. But Senate Republicans filibustered Johnson’s effort to put Abe Fortas in the top job, allowing President Richard M. Nixon to make the pivotal appointment of Warren E. Burger the next year.

Other justices have had more success in timing their departures for political effect. Republican Potter Stewart’s decision to retire in 1981 gave his vacancy to Ronald Reagan to fill (with Sandra Day O’Connor). Byron R. White, at the time the court’s only Democratic appointee, decided to leave in 1993 so Bill Clinton could name his successor (Ruth Bader Ginsburg).

Such episodes illustrate that politics plays a big part not only when justices join the court, but also when they leave. But new details about Chief Justice William H. Rehnquist’s conversations with O’Connor as they both weighed retirement add a new twist: One justice — Rehnquist, in this case — influencing the timing of another’s departure.

The events, as reported by Jan Crawford Greenburg of ABC News in her recent book, “Supreme Conflict,” suggest that the gravely ill Rehnquist might have intentionally misled O’Connor about his own likely tenure so as to ease her off the court earlier than she wanted. And even the hint of manipulation helps make the case for a proposal to limit active service on the Supreme Court to 18 years. By providing for a vacancy every two years, the proposal might reduce the Armageddon-like nature of some recent confirmation battles.

Rehnquist reportedly had his eye on confirmation politics in June 2005. As Greenburg tells the story, O’Connor approached the chief justice earlier in the year as she began thinking about retiring to care for her ailing husband, John. At the time, Rehnquist suggested that they talk again at the end of the term. Rehnquist, suffering from thyroid cancer, knew from his doctors that he probably had less than a year to live, but he had not told his colleagues. When O’Connor approached Rehnquist a second time, he surprised her by saying that he intended to stay for another term. And, according to Greenburg, Rehnquist pointedly added: “I don’t think we need two vacancies.”

In Greenburg’s view, Rehnquist effectively forced O’Connor to retire then or wait two years, longer than she wanted. She took the first option. But then Rehnquist died two months later, creating the situation he had supposedly wanted to avoid.

Greenburg does not accuse Rehnquist of being deliberately misleading, but one conservative commentator saw the implication — and applauded. “If it is true that William Rehnquist effectively pushed Sandra Day O’Connor out the door,” political science professor Matthew Franck wrote for National Review Online, “this fact would count as the last great service he did for his country.”

Most court watchers, however, would probably disapprove of one justice manipulating another’s retirement decision. And Rehnquist’s shielding information about his health had that effect, intentional or not.

Whatever the reasons, the political calculations that retiring justices make would appear to serve no legitimate constitutional purpose. In the modern era, justices often stay or leave depending on who is in the White House. And the president and Senate view each nomination as a chance to shape the court for years to come.

Law professors Roger Cramton and Paul Carrington want to reduce the stakes by setting an 18-year limit on justices’ active service. The still life-tenured justice would then assume “senior status,” available for temporary assignments to lower federal courts or even to the Supreme Court itself if a sitting justice was recused from a case. Cramton and Carrington developed the proposal in part because some aging justices have not carried their fair share of the court’s work. More important, however, they say current arrangements create “incentives for strategic behavior” that may not be in the court’s best interests — or the public’s.

Skeptics argue that this proposal would have cut short the careers of many distinguished justices. But several justices made their marks in fewer than 18 years, including Robert H. Jackson, John Marshall Harlan and Lewis F. Powell Jr. And there seems to be little doubt but that any group of nine justices would have sufficient experience and knowledge to handle the court’s work even if none had served for 20 or 30 years.

The Cramton-Carrington idea has support from law professors spanning the ideological spectrum. Their rationale is that, while no proposal can eliminate politics from Supreme Court successions, an orderly biennial vacancy could help make the court broadly responsive to changing political conditions and also lower the temperature on confirmation battles.

This is an interesting concept, probably worth an airing, but it has little prospect of serious consideration in Congress. Neither political party is likely to see much advantage in such a reform, and most scholars believe it would require a constitutional amendment. Thus, the process of replacing justices of the Supreme Court will probably remain unchanged, with all the resulting human drama that entails.

Kenneth Jost is the Supreme Court editor for CQ Press.