The phrase has been used so many times over so many years to describe the Supreme Court that it is nearly a cliché. Yet the simple words capture an equally simple truth: to find out where the court is on almost any given issue, look for Justice Sandra Day O'Connor.
If you are a lawyer with a case at the court, pitch your arguments to her. If your issue is affirmative action, or religion, or federalism, or redistricting, or abortion, or constitutional due process in any of its many manifestations, you can assume that the fate of that issue is in her hands. Don't bother with doctrinaire assertions and bright-line rules. Be meticulously prepared on the facts, and be ready to show how the law relates to those facts and how, together, they make sense.
And it is because Justice O'Connor has played such a pivotal role on the court for much of her 24-year tenure that her unexpected retirement is such a galvanizing event. Much more than the widely anticipated retirement of the predictably conservative Chief Justice William H. Rehnquist, her departure creates an opportunity for President Bush to shape the court.
The last such defining moment occurred with the retirement in 1987 of Justice Lewis F. Powell Jr., whose position on the court then resembled Justice O'Connor's today. President Ronald Reagan nominated a polarizing conservative, Robert H. Bork, whose defeat by a Democratic-controlled Senate after a protracted battle still resonates today.
A list of the issues on which Justice O'Connor has held the balance of power goes far to explain why holiday weekend preparations screeched to a halt in Washington on Friday morning as word spread of her decision to retire.
Just two years ago, she wrote the opinion for the 5-to-4 majority that upheld affirmative action in university admissions. Earlier, in a series of decisions interpreting the Constitution's guarantee of equal protection, she led or joined 5-to-4 majorities that viewed with great suspicion government policies that took account of race in federal contracting, employment and electoral redistricting. Her view was that the government should not be in the business of counting by race.
But in Grutter v. Bollinger, the University of Michigan case decided in 2003, she became persuaded that affirmative action in university admissions was still justified. "Effective participation by members of all racial and ethnic groups in the civic life of our nation is essential if the dream of one nation, indivisible, is to be realized," she wrote.
Until the pair of Ten Commandments decisions this week, which found her in dissent from the ruling that upheld a Ten Commandments monument on the grounds of the Texas Capitol, she had occupied a central position on the role of religion in public life.
Beginning with her earliest years on the court, Justice O'Connor adopted her own test for evaluating whether government policy amounted to an unconstitutional establishment of religion. Instead of a three-part test that the court used, she asked whether the government policy under review conveyed to nonadherents the message that they were "outsiders, not full members of the political community."
This led her to vote to prohibit public prayer at high school graduations and football games, but to insist on equal access for student religious publications and clubs. In 2002, she voted with the 5-to-4 majority that upheld the use of publicly financed tuition vouchers at religious schools. In her opinion this week concurring with the 5-to-4 majority that declared framed copies of the Ten Commandments hanging in Kentucky courthouses to be unconstitutional, she said the Constitution's religion clauses "protect adherents of all religions, as well as those who believe in no religion at all."
On the other most intensely fought social issue of the day, abortion, Justice O'Connor's successor will not be in a position to move the court away from its support of the core right to abortion, now at 6 to 3. But in the court's last major abortion ruling, five years ago, Justice O'Connor provided the crucial fifth vote to strike down Nebraska's ban on what were called "partial birth" abortions.
She has been a loyal ally of her Stanford Law School classmate Chief Justice William H. Rehnquist in the court's continuing reappraisal of the relationship between the states and the federal government, joining the five-member majority in a series of cases that have insisted on greater respect for the sovereignty of the individual states while limiting the role of Congress.
One of the few federalism cases in which she and Justice Rehnquist parted company came last year in Tennessee v. Lane, on whether states were immune from being sued for failing to make their courthouses accessible to people with disabilities. Justice O'Connor provided a fifth vote against immunity, while Chief Justice Rehnquist dissented. The plaintiff was a man who used a wheelchair and who had been forced to crawl up the stairs to reach the courtroom in a Tennessee county courthouse.
To the extent that Justice O'Connor had an overall judicial philosophy, she might have expressed it most directly in an opinion dissenting from a 1995 decision that authorized public school districts to subject student athletes to drug testing without any suspicion of individual wrongdoing. The policy was justified to deal with rampant student drug use, the district had argued in Vernonia School District v. Acton.
In her dissenting opinion, Justice O'Connor warned that judges should be wary of overreacting to such arguments.
"Some crises are quite real" but some are not, she said. "The only way for judges to mediate these conflicting impulses is to do what they should do anyway: stay close to the record in each case that appears before them, and make their judgments based on that alone."
Sandra O'Connor's pragmatic approach to life and the law was probably born in the stark and isolated desert of the Southwest that she described in vivid detail in "Lazy B," a childhood memoir she published three years ago. The Day family ranch, 250 arid square miles straddling the Arizona-New Mexico border, "was no country for sissies," she wrote.
The house, 35 miles from the nearest town, had neither electricity nor running water. Her companions were horses and ranch hands, and her goal as the first-born child was to be useful around the place and to please her hard-driving, perfectionist father. When things broke, they needed to be fixed. There was little room for discussion and none for theorizing.
Fulfilling her father's own ambition that had been thwarted by the lack of money, she attended Stanford University and Stanford Law School, where she graduated third in the class of 1952 at the age of 22. The top honors in the class went to a World War II veteran more than five years her senior, William H. Rehnquist. He went on to a Supreme Court clerkship. As a woman, she could not get a job with the law firms to which she applied, receiving offers of secretarial jobs instead.
She turned to the public sector as a lawyer for state and local governments, while raising three sons with her husband, John, who had been a fellow law-review editor at Stanford. The couple settled in Phoenix, where civic activities led her to a career in Republican politics. The Arizona governor appointed her to a vacant seat in the State Senate in 1969, and she later twice won election. She became majority leader, the first woman in the country to hold such a high leadership position in a state legislature.
In 1974, she was elected to a seat on the state trial court. Five years later, Gov. Bruce Babbitt, a Democrat, appointed her to the state appeals court, where she was serving when President Reagan, who had promised to appoint a woman to the Supreme Court, chose her in July 1981 for the first vacancy to occur during his term. She was confirmed unanimously, forever to be known as the first woman on the Supreme Court, or F.W.O.T.S.C., as she has put it dryly.
Although hardly a feminist in terms of political activism, Justice O'Connor demonstrated from her earliest years on the court a sensitivity to issues of sex discrimination that she maintained throughout her tenure.
One of her first majority opinions, in 1982, came in Mississippi University for Women v. Hogan. The 5-to-4 decision declared unconstitutional the exclusion of a male applicant from a state-supported, women-only nursing school. Her opinion warned against using "archaic and stereotypic notions" about proper roles for men and women.
On several occasions, including this year, she joined the four more liberal justices to uphold a broad interpretation of a federal statute addressing sex discrimination. In 1999, for example, she wrote the opinion for a 5-to-4 majority in Davis v. Monroe County Board of Education, holding public school districts accountable for one student's sexual harassment of another student.
And during the term that just ended, she wrote the majority opinion in another 5-to-4 decision, Jackson v. Birmingham Board of Education, that expanded the scope of the sex discrimination law known as Title IX to provide protection against retaliation for whistle-blowers who complain about discriminatory practices in schools and colleges.
One exception came in 2000, when she joined Chief Justice Rehnquist's 5-to-4 majority opinion in United States v. Morrison, invalidating a provision of the Violence Against Women Act on the ground that Congress had lacked the constitutional authority to enact the law.
The most famous, or notorious, 5-to-4 opinion in 2000 was, of course, Bush v. Gore, which ended the Florida recount and effectively called the presidential election for George W. Bush. Justice O'Connor joined the unsigned opinion that declared the conditions of the recount to violate the constitutional guarantee of equal protection.
While Mr. Bush was undoubtedly pleased by that decision, he was just as undoubtedly displeased last year when the court refused to accept his administration's position that the federal courts lacked jurisdiction to hear challenges to the open-ended detention of those being held both at the United States naval base at Guantánamo Bay, Cuba, and in military custody in the United States.
"A state of war is not a blank check for the president," Justice O'Connor wrote for the court in Hamdi v. Rumsfeld. She said "history and common sense teach us that an unchecked system of detention carries the potential to become a means for oppression and abuse of others." In a second case decided at the same day last June, Rasul v. Bush, she joined the majority opinion extending federal jurisdiction to the Guantánamo detainees.
During the term that ended on Monday, Justice O'Connor was on the losing side in two major cases: Kelo v. City of New London, which upheld governmental power to use eminent domain for economic development, and Gonzales v. Raich, upholding the federal government's power to enforce federal drug laws in states that permit marijuana to be used for medical purposes.
Justice O'Connor learned she had breast cancer early in the court's 1988 term and underwent a mastectomy and follow-up treatment. She never missed a day that the court was on the bench, and only years later did she reveal publicly, in a talk to other cancer survivors, how stressful the period had been. She also bounced back quickly from an emergency appendectomy.
In recent years, she has maintained an active schedule of public speaking and foreign travel, in addition to writing two books. It was her husband's deteriorating health, not her own brushes with illness, that finally wore down a woman who still proudly refers to herself as a cowgirl.
"She has taught us all," her friend and colleague Stephen G. Breyer said Friday in a statement released by the court.