On June 27, as the Supreme Court ended its term amid rampant speculation about 80-year-old Chief Justice William Rehnquist’s future, his 75-year-old colleague Sandra Day O’Connor was continuing to inch away from her "conservative" past.

In one of the two Janus-faced decisions on the Ten Commandments, the Reagan-appointed O’Connor positioned herself to the left of Clinton-appointed Justice Stephen Breyer. She voted (in dissent) to order removal of a Ten Commandments monument in Texas that he voted to save. Breyer wrote that court-ordered removal "would, I fear, lead the law to exhibit a hostility toward religion that has no place in our Establishment Clause traditions."

It was unusual to see Breyer associating O’Connor (among others) with hostility toward religion. But it has become increasingly common over the past two decades to see the woman who was once routinely (if misleadingly) labeled a member of the Court’s conservative bloc siding with its four most liberal members. She has tipped many a 5-4 decision in their direction, including three big ones this year: the other Ten Commandments case; a decision expanding educational institutions’ liability for sex discrimination; and one overturning a death sentence because of blunders by the defense lawyer.

O’Connor’s leftward drift helps account for the supposedly conservative Rehnquist Court’s surprisingly liberal trend in recent years. So do the similar evolutions of Anthony Kennedy, another Reagan appointee, and John Paul Stevens, a once-moderate Ford appointee who is now the leader of the Court’s liberal bloc. Not to mention the emergence of David Souter as a liberal soon after his appointment by the first President Bush. Kennedy or O’Connor (or both) often leave conservatives gnashing their teeth, by allying with Stevens, Souter, Breyer, and Ruth Bader Ginsburg, the only other Democratic (Clinton) appointee, against Rehnquist, Antonin Scalia, and Clarence Thomas.

This pattern explains the near-desperation with which conservative groups are urging the current President Bush to fill any vacancies with proven, principled, passionate conservatives. For better or worse (or some of each, as I see it), for complex reasons (explored in my July 7, 2003, column), Republican-appointed justices without ideological anchors tend to become more liberal over time.

Justice O’Connor is still conservative on some issues, as recently demonstrated by her passionate dissents in two cases: the 5-4 decision allowing use of eminent domain to take a person’s property and give it to a private company, and the 6-3 decision narrowing states’ rights. (Kennedy joined the liberals in both cases.) O’Connor also takes pains to avoid flat contradiction of her prior opinions. But her current views do contrast with positions that she once took on all four of the biggest culture-war issues: religion, abortion, racial preferences, and gay rights•Religion. O’Connor joined conservatives early on in some church-state decisions that seem hard to reconcile with her more recent opinions and votes. In 1983, she joined a 6-3 ruling that the Constitution permits a state legislature to pay a chaplain to open each day’s session with a prayer; in 1984, she joined a 5-4 ruling that a city may include a Nativity scene as part of an official Christmas display. And she has consistently supported some government aid programs that benefit religious schools.

By 1985, however, O’Connor had begun to side with liberals in attacking governmental actions that appear to endorse religion. She joined in a 6-3 decision that year striking down an Alabama law that allowed a daily minute of silent meditation or prayer in the public schools. Her concurrence condemned any governmental "message that religion or a particular religious belief is favored or preferred." Since then, that view has led her to join decisions banning state-sponsored nondenominational prayers at public school graduation ceremonies (in 1992) and football games (in 2000).

So it was no great surprise on June 27 to see O’Connor joining liberals (including Breyer) in a 5-4 decision ordering removal of framed copies of the Ten Commandments that officials had recently, with a clear religious purpose, put on the walls of two Kentucky courthouses. It was a bit more surprising to see her part with Breyer by voting to order removal of a six-foot-high monument containing the Decalogue from the grounds of the Texas Capitol. That would have doomed dozens of similar monuments around the country. But in the Texas case she was in dissent, with Breyer (and Kennedy) joining the three conservatives. Breyer’s concurrence said the Texas case was different because the monument had stood for 40 years with few objections and conveyed a mainly "moral and historical" message.

• Abortion. In her first two abortion cases, in 1983 and 1986, O’Connor voted (in dissent) to uphold some relatively mild restrictions. More important, she also asserted in her 1983 dissent that states have "compelling interests in the protection of potential human life … throughout pregnancy," and that Roe v. Wade’s three-trimester framework for regulating abortion was "on a collision course with itself." Such statements fostered speculation that she would eventually vote to overrule Roe.

But later in the 1980s, O’Connor began siding with the liberals on some issues. And in 1992, she joined a 5-4 decision reaffirming what the pivotal opinion — co-authored by O’Connor, Kennedy, and Souter — called "the essential holding of Roe v. Wade." While they upheld a 24-hour waiting period and some other previously forbidden restrictions, this was a seismic defeat for the right-to-life movement.

Then, in 2000, O’Connor tipped the balance in a 5-4 decision striking down state laws against the grisly procedure that opponents call "partial-birth abortion." This prompted a cry of betrayal (in dissent) from Kennedy, who had no thought of blessing such an "abhorrent" procedure when he reaffirmed Roe. (The pro-Roe count had become 6-3 when Ginsburg replaced Justice Byron White in 1993.)

• Racial preferences. Never a colorblind-Constitution absolutist, O’Connor hinted as early as 1986 that "promoting racial diversity" on a school’s faculty might justify racial preferences. She also voted in 1987 to uphold some job preferences for women.

But O’Connor joined conservatives in finding serious fault with all seven of the specific racial-preference programs to come before her before 2003. In 1989, in striking down a city’s program setting aside a percentage of its contract dollars for minority contractors, she wrote that such preferences "promote notions of racial inferiority and lead to a politics of racial hostility." She also seemed to suggest that governmental racial-preference programs were unconstitutional except when necessary to remedy proven racial discrimination.

In 2003, however, O’Connor gave racial-preference proponents their greatest victory, by writing a 5-4 decision approving extremely large racial preferences in admissions at the University of Michigan Law School and around the country, in the name of seeking a more diverse student body.

To be sure, O’Connor joined conservatives the same day in striking down (also by 5-4) the all-too-transparent, overtly numerical preferences used by Michigan’s undergraduate school. But the law school decision was far more important. Taken together, while requiring admissions officers to make a pretense of giving each applicant individualized consideration, the decisions upheld what Rehnquist’s dissent demonstrated to be a de facto racial quota.

• Gay rights. In 1986, O’Connor joined an opinion for a 5-4 conservative majority upholding use of a Georgia sodomy law to prosecute two men for having sex in their bedroom and rejecting as "facetious" a claim that due process protected such acts.

But in 1996, O’Connor seemed to reverse course, by joining a 6-3 decision invoking the equal protection clause to strike down a Colorado ballot referendum. It had barred localities (and the state) from including protections for gays in their antidiscrimination laws. And in 2003, she joined a 6-3 decision striking down a Texas law against homosexual sodomy.

The other five justices also reinterpreted the due process clause and overruled the 1986 sodomy decision. O’Connor parted company with them there. She argued for a narrow ruling that Texas (unlike Georgia) had violated equal protection (not due process) by barring only homosexual (not heterosexual) sodomy. But few scholars (if any) take these hairsplitting distinctions seriously.

The bottom line is that Justice O’Connor leans to the liberal side on the most divisive issues that come before the Court. Of course, no matter what she does, many liberals will never forgive her for joining the 5-4 decision that handed the 2000 election to George W. Bush. And they will be more than a little upset if she retires before Bush is gone.