Nonetheless, Justice O’Connor had taken an important step by declaring for the first time that an abortion restriction violated the Constitution. Just two years later, in Planned Parenthood v. Casey, hers was one of the five votes that preserved the right to abortion from what was until then its most serious challenge. Justice Stevens played an important role behind the scenes in framing the question to be decided and in acting as a go-between who had the confidence of both Justice Blackmun, who was distraught at the likelihood that the right to abortion was about to be lost, and the three Republican-appointed justices who unexpectedly proved willing to save it, Justice O’Connor along with Justices Anthony Kennedy and David Souter.

Justice Stevens himself had no particular affection for Roe v. Wade itself, telling his colleagues in a 1985 memo that he didn’t know how he would have voted had he been on the court in 1973. His votes in post-Roe cases early in his tenure alarmed Justice Blackmun. For instance, he voted in dissent to uphold a one-parent consent requirement for minors in a 1977 case from Missouri. In a trio of cases later that year, he voted to uphold state refusals to pay for abortions for poor women.

But his approach started to change as the trickle of new restrictions on abortion became a flood. He voted against parental consent in a 1979 Massachusetts case. A challenge to the Hyde Amendment, a congressional rider on an appropriations bill barring federal Medicaid payments for abortion, reached the court in 1980. Justice Stevens was in the minority that would have struck it down. In the justices’ private conference, according to Justice Blackmun’s notes, Justice Stevens called the measure “a perversion of the spending power” and declared: “We make federal policy by holding a revenue bill hostage — reprehensible!”

He became a trusted adviser to Justice Blackmun, for example persuading his senior colleague to omit from a 1986 decision a direct attack on the Reagan administration’s solicitor general. The administration had, to Justice Blackmun’s great annoyance, urged the court to overturn Roe v. Wade in a case from Pennsylvania in which the state itself had not presented that broad question.

In the index to “The Making of a Justice,” the 531-page memoir that Justice Stevens published this spring, there is no entry for “abortion.” While it’s safe to assume that he didn’t construct his own index, I still found the omission surprising. On reflection, though, the absence seems somehow true to the man.

He didn’t think in abstract categories. Cases were problems to be solved, not theories to be expounded upon. Most of the decisions I’ve referred to here are in his book, but not all of them. The memoir is organized chronologically rather than topically. To figure out what Justice Stevens thought about a particular issue, the reader has to find the cases, one at a time for 35 years. What led a troubled country to note in more than a passing way the death of a 99-year-old man was, I think, the realization that we’re not likely to see that kind of Supreme Court justice any time soon.