he battle over abortion, now flaring again with the prospect of change at the Supreme Court, has been raging for so long that its origins have been largely lost to time and myth. During the 32 years since the court decided Roe v. Wade, the right to abortion has become so entwined, both in political discourse and in the public mind, with women's rights in general that it is tempting to assume that the middle-aged men who voted in 1973 to overturn state abortion laws thought they were striking a blow for women's equality.

The collected papers of Roe's author, Justice Harry A. Blackmun, show a more complicated reality, illuminating what turns out to be a highly tenuous connection between the abortion cases and the cases on women's equality that reached the Supreme Court simultaneously in the early 1970's.

The Library of Congress, following Blackmun's instructions, opened his papers to the public in March of last year, on the fifth anniversary of his death. The voluminous files, which occupy more than 600 feet on the shelves of the library's manuscript division, include not only detailed records of the business the court conducted during the 24 years he served there, but also memos and annotations that reveal Blackmun's own efforts to grapple with the issues presented by the thousands of cases he encountered. The record of his personal responses to the briefs and arguments in many of the cases indicates a kind of interior monologue that ranged across the court's docket. His papers tell an intensely personal story even as they open a window on a period of Supreme Court history that is in many ways as pertinent today as it was when he and his fellow justices were trying to understand and respond to a changing world.

Named to the court by Richard Nixon, Harry Blackmun took his seat in June 1970. Two abortion cases arrived at the court's door in the following months: Roe v. Wade, challenging a Texas law that made abortion a crime in nearly all instances, and Doe v. Bolton, a case from Georgia, where a new ''reform'' law permitted some abortions, though under stringent regulations. Federal courts in both states had ruled that the Constitution gave women a right to decide whether to carry a pregnancy to term.

For Blackmun, who had spent nine years as general counsel to the Mayo Clinic and who held the medical profession in high regard, state laws that criminalized abortion were indeed troublesome -- not, particularly, because they interfered with the rights of women but because they put doctors at risk for using their best judgment in treating their pregnant patients. Among Blackmun's files is an article from the Mayo alumni magazine by Dr. Jane E. Hodgson, a prominent Minnesota obstetrician and Mayo alumna who had been prosecuted for performing an abortion on a patient who contracted German measles early in pregnancy, a circumstance known to carry a high risk of birth defects. ''Someday, abortion will be a humane medical service, not a felony,'' Dr. Hodgson boldly predicted. Leading medical organizations had recently dropped their longstanding opposition to legal abortion and filed briefs with the court depicting criminal abortion laws as a threat to public health.

The degree to which these developments influenced both Blackmun and the other members of his 7-to-2 majority in Roe v. Wade is strikingly clear from the opinion itself. ''The decision vindicates the right of the physician to administer medical treatment according to his professional judgment,'' Blackmun wrote in a key summary paragraph. To the extent the decision vindicated the rights of women, it was by proxy, through their (mostly male) doctors.

Harry Blackmun served another 21 years on the court after Roe v. Wade, retiring in 1994 at the age of 85. By then, he had long since become an icon of feminism. Just as he was reviled by opponents of abortion, he was treated worshipfully by women's rights groups. Yet Blackmun came slowly to the cause of women's equality, and his papers show just how improbable an icon he was.

t was not that Blackmun was hostile to women's rights. He scarcely could have been, as the father of three daughters, one of whom eventually became a lawyer. When the family lived in Rochester, Minn., home of the Mayo Clinic, his wife, Dorothy, was a partner in a clothing business called Designing Women. At a time when many men of his generation disregarded women's professional accomplishments, Blackmun appreciated them. By the time he retired, he had hired more female law clerks than the other sitting justices combined, and during his last 10 years on the court, a majority of his clerks were women.

But when Ruth Bader Ginsburg, who was the director of the American Civil Liberties Union's Women's Rights Project in the 1970's, began bringing cases to the court as part of a carefully constructed litigation campaign, Blackmun was unimpressed. The cases often struck him as contrived, with petty claims and overbearing arguments. In one of the earliest cases, Reed v. Reed, the court was asked to invalidate an Idaho law that gave automatic preference to men over women for selection to administer an estate. Ginsburg did not argue the case, but she worked on a brief for the appellant, Sally Reed.

At the time, the court's precedents did not recognize sex discrimination as presenting any special constitutional concern; for the government to prefer one sex over the other was no more problematic than to favor tall people over short or young over old, permissible as long as the government could articulate a ''rational basis'' for the policy. The so-called rational-basis test, instructing judges to give maximum deference to whatever explanation the government provided, is scarcely a test at all, because the government nearly always prevails.

Ginsburg's goal was to persuade the Supreme Court to accept a different paradigm: to see sex discrimination as analogous to racial discrimination and to declare that under the 14th Amendment's guarantee of equal protection, official policies that discriminated on the basis of sex were presumptively unconstitutional. Under the court's precedents, a policy that treats racial groups differently is considered ''suspect'' and receives the most searching scrutiny from judges -- ''strict scrutiny'' -- and can be upheld only if the government demonstrates that it serves a ''compelling state interest.'' Policies that receive strict judicial scrutiny are not invariably found unconstitutional -- two years ago, the Supreme Court accepted the University of Michigan's justification for affirmative action in admission to its law school -- but they nearly always are.

Blackmun was initially skeptical of the challenge to the Idaho probate law. ''This case, of course, is a test case and much ado about nothing,'' he wrote in a memo to himself before the argument in October 1971, noting that the estate in dispute amounted to less than $1,000. He described Ginsburg's brief as ''mildly offensive and arrogant'' and ''a very lengthy brief filled with emotion and historical context about the inferior status of women.'' At 68 pages, the brief was indeed longer than most, although not drastically so, providing dramatically worded background information for what Blackmun saw as ''a very simple little case.'' The Idaho probate code commanded the ''subordination of women,'' the brief stated. ''American women have been stigmatized historically as an inferior class and are today subject to pervasive discrimination. . . . A person born female continues to be branded inferior for this congenital and unalterable condition of birth.''

Yet even as he criticized Ginsburg's brief, Blackmun was attentive to it; almost despite himself, his response to the case was shaped by her presentation, as his memo makes clear. The memo, barely four pages long and internally inconsistent in places, shows a judge wrestling with his instincts and biases in order to get to the heart of a challenging legal problem. ''All in all, I am inclined to feel that sex can be considered a suspect classification just as race,'' he wrote. ''This does not mean that every statute which makes a distinction based on sex is automatically invalid. It merely sets as the starting point the proposition that such a distinction is suspect and strong justification is needed to uphold it. There can be no question that women have been held down in the past in almost every area.''

In the end, Blackmun persuaded himself that the Idaho law was indeed unconstitutional. ''We certainly could write a fairly brief and simple opinion accomplishing that very result,'' he concluded in his memo. ''I would hope that we do not get into a long and emotional discussion about women's rights.''

The court's unanimous decision in Reed v. Reed, in a six-page opinion written by Chief Justice Warren E. Burger, reflected little of the deeper debate. Idaho's preference for men over women to administer estates was arbitrary and unreasonable, the court held. The law failed to meet even the rational-basis test, relieving the justices of the need to decide whether sex-discrimination claims should be evaluated under a more searching standard -- whether sex, like race, should be deemed a ''suspect classification,'' presumably unconstitutional as a basis for government policy.

The court was only one front in the struggle for women's rights during those years. Congress approved the proposed Equal Rights Amendment in 1972 and sent it to the states for ratification. If three-quarters of the legislatures ratified it, the amendment would accomplish what Ginsburg's brief had asked the court to do in Reed v. Reed and make discrimination against women subject to strict judicial scrutiny. Soon, the highly charged politics of the amendment and the uncertainty within the court about how far and how fast to move the law converged in a new case. Frontiero v. Richardson was a suit by an Air Force officer for the right to claim her husband as a dependent for the purpose of obtaining housing and medical benefits, although the husband was not financially dependent on her. Under the laws governing military benefits, a serviceman could automatically claim his wife as a dependent, regardless of their relative circumstances, while a woman could claim her husband only if she brought in more than half the family income.

''This must be stricken down,'' Blackmun wrote in his notes before the January 1973 argument. The question is ''by what route and how far.'' That, indeed, was the question: whether to accomplish the goals of the Equal Rights Amendment by judicial decree and make its ratification unnecessary. The battle inside the court went back and forth for weeks. All the justices except William H. Rehnquist agreed that the distinction between servicemen and servicewomen was unsustainable. Justice William J. Brennan Jr. wanted to use the case to establish strict scrutiny, arguing that Reed v. Reed had done so implicitly, in its rejection of administrative convenience as an acceptable rationale for the state's policy. Burger, who wrote the Reed opinion, vigorously disagreed. ''Some may construe Reed as supporting the 'suspect' view but I do not,'' he wrote to Brennan. ''The author of Reed never remotely contemplated such a broad concept, but then a lot of people sire offspring unintended!''

In the new case, Ginsburg filed a 70-page brief for the A.C.L.U., urging the court to adopt strict scrutiny. James W. Ziglar, one of Blackmun's law clerks, found the brief persuasive and urged the justice to ''go the whole route and find that sex is a 'suspect classification.' '' But Blackmun resisted.

Roe v. Wade had been decided barely six weeks earlier, but no member of the court referred to it as the sex-discrimination debate unfolded. ''After some struggle, I have now concluded that it is not advisable, and certainly not necessary, for us to reach out in this case to hold that sex, like race and national origin and alienage, is a suspect classification,'' Blackmun wrote to Brennan. ''It seems to me that Reed v. Reed is ample precedent here and is all we need and that we should not, by this case, enter the arena of the proposed Equal Rights Amendment.''

Brennan, monitoring the amendment's sagging fortunes, argued that the time for the court to act was now. The Equal Rights Amendment had already been rejected by 11 state legislatures, he pointed out, and two more would be sufficient to kill it. Three other justices, William O. Douglas, Byron R. White and Thurgood Marshall, agreed, but Brennan could not find a fifth vote for strict scrutiny in the Frontiero case. Blackmun concurred only in the judgment that military benefits had to be equal, as did Burger, Lewis F. Powell Jr. and Potter Stewart. Rehnquist, alone, dissented. So while the court voted 8 to 1 that the distinction in benefits was unconstitutional, the Frontiero decision, issued May 14, 1973, did not establish a new standard of review for sex discrimination.

The next term, the court heard another of Ginsburg's cases, Kahn v. Shevin. Representing a male plaintiff this time, Ginsburg was challenging a Florida law that gave an annual automatic $500 property-tax exemption to widows but not to widowers. The Florida Supreme Court had upheld the law, finding that it bore a ''fair and substantial relation'' to the goal of reducing ''the disparity between the economic capabilities of a man and a woman.'' To a majority of the court, including Blackmun, that reasoning seemed to produce a sensible outcome. ''Too smart,'' was the comment he wrote to himself on Ginsburg's argument; at the same time he gave her argument a grade of B, higher than the C he gave her opponent, an assistant state attorney general. (Blackmun used various measures over the years to grade attorneys' arguments, sometimes giving letter grades and sometimes numbers on a variety of scales.)

Brennan, Marshall and White voted to apply strict scrutiny and overturn the Florida law, but Blackmun agreed with Douglas that the law was ''reasonably designed to further the state policy of cushioning the financial impact of spousal loss upon the sex for whom that loss imposes a disproportionately heavy burden,'' as Douglas wrote in the almost cursory four-page opinion the court issued in April 1974. Before signing on to the final draft of the opinion, Blackmun objected to a footnote that contained an oblique and, in Blackmun's mind, gratuitous reference of Roe v. Wade. Defending his rejection of strict scrutiny, Douglas tried to show that there was nothing in Roe v. Wade that required it; that decision was about women as potential mothers, not women versus men, he maintained. ''Gender has never been rejected as an impermissible classification in all instances,'' Douglas wrote in his draft opinion in the new case. ''When we had before us Roe v. Wade, the court proceeded to treat the abortion problem on the basis that it pertained to the prerogative of the mother in which the putative father had no concern.''

Blackmun was ''somewhat disturbed'' by the reference, he told Douglas, because in Roe itself, the court had explicitly deferred consideration of whether fathers had any rights in the abortion context. Douglas's reference was ''not consistent'' with the court's decision to avoid the issue, Blackmun said. Douglas responded that Blackmun's point was ''very well taken'' and removed the reference.

That it took 14 months after Roe v. Wade for any mention of abortion to seep into the court's evolving conversation about sex discrimination showed how unrelated the two subjects appeared to the justices. Blackmun and the other justices were extremely reluctant to place a label of sex discrimination even on a policy that involved pregnancy -- mandatory unpaid leaves for public schoolteachers before their pregnancies began to ''show'' -- and which struck most of them as troubling and unfair. ''It is easy to say initially that any regulation which relates to pregnancy is automatically and per se sex discriminatory,'' Blackmun wrote in his memo before the argument in Cleveland Board of Education v. LaFleur, decided in January 1974. ''I am not at all certain that this is necessarily so. Actually, what the regulation does is to draw distinctions between classes of women, that is, those who are pregnant and those who are not pregnant, rather than between male and female.'' Similarly, an Army regulation prohibiting beards, he noted, could not be viewed as sex discrimination, because it applied to only men. At the top of this typewritten memo, Blackmun added a handwritten note: ''N[ot] sex related.'' He eventually joined Potter Stewart's majority opinion that invalidated the mandatory-leave policy on the basis of due process -- that forcing a woman to stop working by her fifth month of pregnancy was ''arbitrary'' -- rather than equal protection; the word ''discrimination'' did not appear in Stewart's opinion.

Two years later, the deferred question that Blackmun had discussed with Douglas, whether a state could give a man veto power over his wife's decision to have an abortion, reached the court in Planned Parenthood of Central Missouri v. Danforth. Blackmun wrote the majority opinion finding a husband's veto unconstitutional, but his tone was detached. Preparing for the argument, he read a brief that framed the issue in overtly feminist terms, and his memo disparaged the presentation. ''This brief, of course, presents the extreme on the female side,'' he wrote to himself. The court's abortion and sex-discrimination cases were still running on their parallel tracks.

Ginsburg was back before the court in the 1975 term, in Weinberger v. Wiesenfeld, a challenge to a provision of the Social Security Act that made still another distinction between men and women in calculating government benefits. If a male wage earner died, both his widow and their minor children would receive benefits. But if the wage earner was a woman, benefits would go only to her children and not her husband. The difference was based on the government's assumption that a father was more likely to be a family's breadwinner and would not need the support of his wife's Social Security benefits. Ginsburg's client, Stephen C. Wiesenfeld, was a self-employed consultant whose wife, a schoolteacher, provided most of the couple's income. She died in childbirth, and he was told that while their newborn son was eligible for benefits, he was not.

The case initially struck Blackmun as little different from Kahn v. Shevin, in which the court recently upheld Florida's preferential tax exemption and rejected Ginsburg's argument on behalf of her male client. In his memo, Blackmun said the premise behind the federal law was sound. Change should come from Congress, not the court. ''That is where it belongs really if changing times are equalizing income as between men and women. . . . So long as the objective of the differential is to alleviate need, I suspect that we shall have to hold that the differential is not unconstitutional.'' His law clerk, Richard Blumenthal, agreed, observing to Blackmun that ''women are more likely to be needy, even in this increasingly liberated age.''

But as Blackmun listened to Ginsburg, he began to change his mind. ''It is a good clean case, factually,'' he noted to himself during the argument, and the distinction the law made appeared ''useless.'' He gave Ginsburg a B. After initially voting to uphold the law, he eventually joined Brennan's majority opinion that found the sex-based distinction ''entirely irrational.''

ven so, Blackmun retained his skepticism. In November 1980, in anticipation that a woman might join their ranks someday, the justices voted to drop the traditional ''Mr. Justice'' in formal court papers. Blackmun made his objections known within the court. ''We seem to be eliminating, step by step, all aspects of diverseness, and we give impetus to the trend toward a colorless society,'' he wrote to his colleagues in protest. Ten months later, Sandra Day O'Connor did join the court. It was far from clear what difference she might make on the issue of sex discrimination. O'Connor had not presented herself as a feminist, and Blackmun did not expect her to be one. The first test came in her first term, when the court accepted a challenge to the constitutionality of a state-supported single-sex college, the Mississippi University for Women.

Joe Hogan, who was denied admission to the university's nursing school, sued and won a ruling from the federal appeals court in New Orleans that his exclusion was unconstitutional. The university appealed. One of Blackmun's law clerks, Kit Kinports, urged him to vote to affirm the decision. ''The opinion need not be a sweeping one,'' she wrote reassuringly. There would be ''very little practical impact'' because there were only two other single-sex state universities in the country. Blackmun was unpersuaded. He would vote to reverse ''despite my clerks,'' he wrote in his memo before the argument in March 1982. The state's defense of its women-only program sounded plausible. ''I am not qualified to say single-sex situation cannot be educationally sound,'' he noted.

During the arguments in Mississippi University for Women v. Hogan, Blackmun jotted down his prediction that O'Connor would join him in a vote to reverse. But he was wrong. At the conference, the justices were closely divided. O'Connor, Brennan, White, Marshall and John Paul Stevens voted to affirm, while Blackmun, Burger, Powell, and Rehnquist voted to reverse. The case engaged the court on an emotional level that had been missing from the cases parsing the finer points of Social Security law. ''We all belong to all-male organizations,'' Burger observed during the conference, according to Blackmun's notes. Powell, who had graduated from Washington and Lee University when it was all-male, said that ''all Powells have gone to single-sex schools.'' They were ''perfectly legitimate,'' he said.

Assigned by Brennan to write the majority opinion, O'Connor circulated a draft that emphasized the anachronistic nature of the university's stated mission, to train ''the girls of the state'' for the ''practical affairs of life.'' Excluding men from the nursing program ''tends to perpetuate the stereotyped view of nursing as an exclusively woman's job'' and makes that view a ''self-fulfilling prophecy,'' O'Connor wrote. Kinports, Blackmun's clerk, urged him to join O'Connor's ''persuasive, analytical and exceedingly narrow opinion,'' but he held firm. His dissenting opinion warned against ''needless conformity'' in the name of equality. ''I have come to suspect that it is easy to go too far with rigid rules in this area of claimed sex discrimination, and to lose -- indeed destroy -- values that mean much to some people by forbidding the State to offer them a choice while not depriving others of an alternative choice.''

andra Day O'connor surprised Blackmun in the Mississippi case, but there was a bigger challenge to come: her vote the next year in her first abortion case, Akron v. Akron Center for Reproductive Health. O'Connor dissented from a 6-to-3 majority decision that struck down a package of regulations that Akron, Ohio, had adopted to discourage abortions. The majority held that the regulations, including a 24-hour waiting period, were inconsistent with Roe v. Wade. O'Connor's dissenting opinion not only disputed that conclusion, but also took issue with Roe v. Wade itself. Predicting that the date of fetal viability would move ever closer toward the beginning of a pregnancy, she proclaimed Roe's analytic framework to be ''clearly on a collision course with itself.'' Abortion restrictions should be upheld, O'Connor wrote, as long as they did not present an ''undue burden,'' a standard that would strip the right to abortion of its status as ''fundamental.''

Just past its 10th anniversary, Roe was in trouble. And it was in the course of protecting Roe that Blackmun began to see himself as protecting the rights of women.

A series of decisions on whether poor women were entitled to publicly financed abortions had already served to shift Blackmun's focus. He had argued, unsuccessfully, that the government's refusal to pay for abortions for poor women was an indirect circumvention of Roe v. Wade that the court should not permit. His concern in these cases was not doctors, but women -- poor, pregnant, alone, in need. In Thornburgh v. American College of Obstetricians and Gynecologists, in 1986, the justices voted by only a 5-to-4 majority to strike down a series of anti-abortion regulations from Pennsylvania. As the Roe majority shrank, with Burger having defected and O'Connor having joined the court, Blackmun's previously clinical tone was replaced by something close to passion. Blackmun's majority opinion bore little resemblance to the doctor-centric tone of Roe v. Wade. ''Few decisions are more personal and intimate, more properly private or more basic to individual dignity and autonomy,'' he wrote, than a woman's decision to terminate her pregnancy.

By 1989, when the court in Webster v. Reproductive Health Services upheld a series of anti-abortion regulations in a Missouri statute, Blackmun was in dissent. Now, as he contemplated the prospect that Roe itself would soon be overturned, his entire focus was on women. ''I fear for the liberty and equality of the millions of women who have lived and come of age in the 16 years since Roe was decided,'' he wrote. For Blackmun, the abortion and sex-discrimination cases, having run on parallel tracks for years, were about to converge in the embrace of reproductive freedom as an essential aspect of women's equality.

In 1992, the court finally confronted Roe directly in Planned Parenthood of Southeastern Pennsylvania v. Casey. At issue was a Pennsylvania law that imposed a series of abortion regulations, similar to those in other recent cases. The Webster case three years earlier indicated that these were likely to be upheld. Further, two of Roe's strongest supporters, Justices Brennan and Marshall, had retired since the Webster decision, succeeded by David H. Souter and Clarence Thomas. Planned Parenthood v. Casey was argued in April 1992. As the country waited for an answer from the court and with a presidential campaign well under way, advocates on both sides gave Roe little prospect of surviving. But it did, with the crucial participation of three Republican-appointed justices: Souter, Anthony M. Kennedy and Sandra Day O'Connor. They had considered the question, the three wrote in an unusual joint opinion, and had concluded that ''the essential holding of Roe v. Wade should be retained and once again reaffirmed.'' With Blackmun and John Paul Stevens concurring separately, that meant five votes for the right to abortion. Blackmun's opinion read like a women's rights manifesto:
 

A State's restrictions on a woman's right to terminate her pregnancy also implicate constitutional guarantees of gender equality. State restrictions on abortion compel women to continue pregnancies they otherwise might terminate. By restricting the right to terminate pregnancies, the State conscripts women's bodies into its service. . . . The State does not compensate women for their services; instead, it assumes that they owe this duty as a matter of course. This assumption -- that women can simply be forced to accept the ''natural'' status and incidents of motherhood -- appears to rest upon a conception of women's role that has triggered the protection of the Equal Protection Clause.

And then Blackmun did something remarkable. He cited Mississippi University for Women v. Hogan, O'Connor's opinion on single-sex education that had provoked his heartfelt dissent 10 years before. The convergence was complete.

uth Bader Ginsburg joined the court the next year. Blackmun was wary. Ginsburg had criticized Roe -- its analysis, not its outcome -- in a highly publicized lecture in which she asserted that the court had moved too far and too fast in issuing a decision and that ''a less encompassing Roe'' might have ultimately done more to promote abortion rights. Further, she and Justice Antonin Scalia, Roe's most outspoken critic on the court, were known to be friends from their years together as Court of Appeals judges. ''Can she stand up to A.S.?'' Blackmun noted to himself after her nomination.

But Ginsburg's first term -- which proved to be Blackmun's last -- demonstrated that she was not about to temper her views to Scalia's liking. The court accepted J.E.B. v. Alabama, a case on whether the Constitution permitted lawyers to strike potential jurors on the basis of sex. Eight years earlier, the court barred race as a factor in jury selection. Applying the same principle to sex was ''inevitable,'' Blackmun wrote in his memo before the argument in November 1993. The conference discussion after the argument was lively, with Scalia particularly energized. To bar the use of sex in jury selection would be a ''terrible thing,'' he said, the ''most radical decision in 30 years.'' The vote to extend the race-discrimination precedent to sex was 6 to 3, with Scalia, Rehnquist and Thomas in dissent. As the senior associate justice, Blackmun had the power to assign opinions when the chief justice was in dissent. He assigned this case to himself.

His opinion traced the history of the court system's discrimination against women, citing four of the cases Ginsburg had brought to the Supreme Court. His draft included a footnote on whether claims of sex discrimination should be subject to strict judicial scrutiny; although it was not necessary to decide that question in this case, because sex-based jury selection could not be sustained even under a lower standard, the strict-scrutiny question remained open for future cases. The footnote was a bouquet to his new colleague -- offering the prospect that the battle she had lost so long ago might be won yet -- and Ginsburg understood it as such. ''I am pleased to join your opinion and particularly appreciate footnote 6,'' she wrote to Blackmun.

In an angry dissent, Scalia accused the majority of adopting a ''unisex creed,'' of obscuring its reasoning behind ''anti-male-chauvinist oratory'' in order to ''pay conspicuous obeisance to the equality of the sexes.'' Sandra Day O'Connor joined Blackmun's opinion and filed a separate concurring opinion as well. Ruth Ginsburg said nothing. She had no need to. Harry Blackmun had, finally and improbably, spoken for her.