This fall, the Supreme Court enters a new era. No more will William Rehnquist stare coldly down at lawyers from the center chair. Instead, John Roberts will amiably but firmly interrogate them. And no more will Sandra Day O’Connor, sitting next to the Chief Justice, crisply ask her probing questions.

Instead, Samuel Alito will politely address his from the far right end of the bench.

The next few years may see even more changes, for six of the nine Justices are over 65; John Paul Stevens, the court’s eldest member, is 86. On the other hand, federal Justices tend to live a long time and, unlike judges everywhere else in the world, need never retire. Overall, there have been only 110 Justices in our entire history. The last ten Justices to leave our Supreme Court served an average of twenty-six years; the shortest tenure was fifteen years. Four of them served over thirty-one years; Stevens is now in his thirty-first. Allowing public officials to stay in office so long, subject to no accountability and virtually no check, is a peculiar–and deeply undemocratic–feature of American democracy. No other democracy tolerates such lengthy judicial tenure. The anomaly of our system is compounded by the fact that someone can be handed such power by a partisan Senate vote of just 51 to 50 or, as was true for Clarence Thomas, 52 to 48.

And yet, except for some particularly controversial nominations like Robert Bork’s, most Americans do not seem to care. There is a widespread impression that the President is entitled to a strong presumption in his favor for judicial nominations, even for the High Court. Not so, for the judiciary is not an arm of the executive. It is an independent third branch, designed to check both the President and Congress when necessary, equally and impartially. Since the appointment process is the only way we have for achieving that impartiality, the Senate and the President must be equal parties in that process.

This was thoroughly understood in the eighteenth and nineteenth centuries, when even George Washington had a nominee rejected; during the nineteenth century, approximately one-third of all Supreme Court nominations were rejected, withdrawn or otherwise not confirmed. Only in the twentieth century has the presidential presumption become so strong. As a result, most nomination hearings today are useless rituals. If the nominee has done or said anything that is remotely controversial, he or she declares that it says nothing about his or her current views and solemnly promises fidelity to judicial restraint and to precedent, and the senators get free television time for some–usually fatuous–speech-making.

Where Supreme Court nominees are concerned, this public airing is also unnecessary. Except with someone relatively unknown, like David Souter, the nominee’s record usually reveals who and what the nominee is. What the senators don’t already know, they won’t find out, for if the nominee is at all controversial, he or she will have been well coached either to evade their questions or to give them answers they want to hear.

There were no secrets, for example, about Roberts or Alito. In 1985 Alito wrote that “the greatest influences on my views were the writings of William F. Buckley, Jr., the National Review…Barry Goldwater’s 1964 campaign” and “disagreement with the Warren Court decisions particularly in the areas of criminal procedure, the Establishment Clause and apportionment.” His entire career thereafter was consistent with that early declaration. Roberts, more discreet, said almost nothing publicly about his personal views, even though he’d devoted his entire career in high government posts, private practice and on the bench to promoting right-wing causes.

Not surprisingly, Roberts and Alito, during their first months on the Supreme Court, cast votes consistent with their prior records. In the last term, Roberts voted with Antonin Scalia and Clarence Thomas 95 percent and 92 percent of the time, respectively; in his first five months on the Court, Alito voted 87-95 percent of the time with Scalia, Thomas and Roberts. Having been elevated to the pinnacle of their profession because of their ideological purity and reliability, why should they change?

The outcomes of few important cases were affected, however. For example, in Hamdan v. Rumsfeld, the military commissions case in which George W. Bush appeared to be channeling Louis XIV, Alito voted with Scalia and Thomas (Roberts recused himself, having backed the government over Hamdan as an appeals court judge), but Kennedy refused to join them and made a majority (5-3) against Bush. In an important 5-4 environmental decision upholding federal power over certain wetlands, Rapanos v. United States, Alito again joined the Scalia-Roberts-Thomas bloc, but again Kennedy defected. And in the Oregon physician-assisted-suicide case, Kennedy again joined the liberals, with O’Connor, making a 6-3 majority; Roberts again sided with Thomas and Scalia. Nevertheless, Kennedy remains on the whole quite conservative, and on such issues as late-term abortions and affirmative action in education (both matters are scheduled for argument this term), national security, capital punishment, religious displays, disability rights and women’s rights, where O’Connor sometimes switched sides to make a narrow liberal majority, Alito will probably move the Court further to the right.

It is, of course, possible that either Alito or Roberts will disappoint Bush’s expectations–but it’s not likely. Despite the conventional mythology, most Justices vote as their backers expect. As Lee Epstein and Jeffrey Segal point out in their short but useful book on politics and the federal courts, Advice and Consent: The Politics of Judicial Appointments, “by and large, presidents are successful with their appointees…. More often than not, they [the Justices] vote in ways that would very much please the men who appointed them.” This is because, as they emphasize, throughout the entire process–when a Justice retires, who is nominated and who wins confirmation–“politics pervades.”

There are, however, exceptions, like David Souter and (to a far lesser degree) Sandra Day O’Connor, who are the subjects of two new biographies. Political science professor Tinsley Yarbrough’s welcome and informative biography David Hackett Souter: Traditional Republican on the Rehnquist Court provides one of the few sources of information about the least known Justice in recent memory. Few knew anything about Souter when he was nominated by President George H.W. Bush in 1990 on the recommendation of former New Hampshire Governor John Sununu, Bush’s Chief of Staff. Sununu, it turns out, didn’t know him very well either. When Souter was nominated, Sununu reassured nervous allies that he would be a “home run” for the right. As we now know, Sununu could not have been more wrong. Souter has become one of the strongest liberal voices on the Court.

A careful reading of Souter’s confirmation hearing might have alerted some astute observers that he was not quite the conservative team player Sununu imagined. When asked if he had any concerns about “rights created by the court,” Souter said no. He supported affirmative action and declared that when the legislature leaves a “vacuum,” judges “have got an obligation to come down with practical decrees that implement…rights.” He stunned Dixiecrat Senator Strom Thurmond by asserting that the Tenth Amendment, which reserves to the states the powers not delegated to the federal government, “is something that we cannot look at with the eyes of the people who wrote it.” These remarks implied little, however, as to how Souter would later vote. This is probably because before going on the Supreme Court, he had rarely ruled on the constitutional and statutory issues that make up the High Court docket. As one close friend put it, “No one knows how David Souter will vote–no one. David Souter does not know.”

Sandra Day O’Connor is a very different case. As USA Today correspondent Joan Biskupic makes clear in her smoothly written and insightful biography Sandra Day O’Connor: How the First Woman on the Supreme Court Became Its Most Influential Justice, O’Connor is a politician, a pragmatist more interested in building winning coalitions than in doctrinal development. She entered Republican politics early and used her intellect, her suburban-lady charm and her genuine kindliness to impress both her peers and those in power. As Biskupic says, “Never one to upend the system, she worked within it to get what she wanted.”

During her first twenty years on the Court, O’Connor was a thoroughly reliable member of the Court’s right wing–something that is often forgotten today. In almost every close case involving racial justice, she came out against the minority litigant; she tried, unsuccessfully, to deny children of illegal immigrants a free public education, and she wrote the key opinions cutting back the availability of habeas corpus. She also sided consistently with business interests and assumed a leading role in the conservative crusade to shrink the federal government’s Commerce Clause and other powers, and provided the fifth vote to allow homosexual intercourse to be made criminal. And while reaffirming Roe v. Wade in 1992, she allowed states and localities to raise almost insurmountable obstacles for young, rural or low-income women seeking an abortion. The only discrimination that appeared to raise her indignation was against women, perhaps because of her unpleasant encounters with sexism after she graduated from law school.

O’Connor remained conservative to the end of her career–in her last three full years on the Court she voted most often with Rehnquist, as she always had. Still, after Bush v. Gore she moved closer to the center in significant ways. The year after Bush v. Gore, she joined in barring the death penalty for retarded defendants, reversing a 1989 decision she had written for the Court. (In 2005, however, she tried–unsuccessfully–to retain the death penalty for juveniles.) In 2003 she voted to overturn the criminalization of male homosexual intercourse, though on a narrower basis than the Court majority. In perhaps her most notable shift, she drafted a 5-4 majority decision allowing racial preferences in higher education under certain conditions. And two years ago she wrote eloquently for a four-person plurality, rejecting the President’s demand for unchecked power to detain American citizens in time of war.

Throughout her career, Biskupic writes, O’Connor followed a pragmatic, incremental approach focused on the facts of each case, designed to build coalitions rather than develop strict doctrinal rules. This approach has drawn both criticism and praise. Among its admirers is Cass Sunstein, a University of Chicago law school professor whose recent book Radicals in Robes: Why Extreme Right-Wing Courts Are Wrong for America, advocates a minimalist approach like O’Connor’s.

Sunstein’s case for minimalism is presented as part of a methodological discussion that purports to be neither political nor ideological but rather an objective view about how our Constitution should be interpreted. Scalia, Thomas et al. are described as “fundamentalists” who want to restore the original meaning of the Constitution; the Warren Court, its supporters and successors are labeled “perfectionists” who want to “make the [Constitution] as good as it can be.” Both are found wanting. “Minimalists”–Sunstein and O’Connor–try “to reach incompletely theorized agreements” leaving “most fundamental questions…undecided.” These have it right, according to Sunstein.

Most of the book is devoted to attacking the fundamentalists’ recent victories. Although Sunstein runs through the usual analytical critiques of Scalia’s and Thomas’s “original meaning” philosophy and their not infrequent inconsistencies, his primary criticism, reiterated constantly without much explanation, is simply that the fundamentalists’ views “produce a far worse system of constitutional law” and lead to “intolerable consequences.” What makes the system “worse” and “intolerable” is assumed to be self-evident.

As for the “perfectionists,” Sunstein acknowledges that “perfectionist” courts in South Africa and elsewhere have abolished capital punishment and created a vast array of civil and social rights. In those countries, he concedes, that may be acceptable, but for the “contemporary United States…minimalism is best and…both fundamentalism and perfectionism are dangerous…. Each of us ought to have a little voice in our heads cautioning: I might be wrong.” But that’s always true, everywhere, and if the fear of being wrong had stopped the Warren Court and its successors, we might still be living with “separate but equal,” legal discrimination against women, official school prayers, unequal voting districts, bans on contraception and abortion, criminalization of homosexual intercourse, fewer protections for speech and much more that Sunstein considers “intolerable.” All were outlawed by “perfectionist” judges.

In fact, Sunstein criticizes almost none of the Warren Court’s decisions and reserves his scorn for such “perfectionist” claims as the right not to wear seat belts, to use medicinal drugs not authorized by the Food and Drug Administration, to hire or be a prostitute, and to marry a person of the same sex. Except for the last, however, liberals have not sought any of these, and, in any event, it will probably be a long time before the federal courts deal with same-sex marriage–the Massachusetts and other decisions allowing same-sex marriage were decided under state Constitutions, and most of them have been overturned.

Minimalism, on the other hand, has done a great deal of harm. “Minimalist” decisions like Brown v. Board of Education II (1955) allowed gradual school desegregation and produced spurious “freedom of choice” plans that delayed Southern school desegregation for fourteen years. The Casey abortion decision, discussed earlier, which abandoned the strict “perfectionist” approach of Roe v. Wade, and barred restrictions on abortion only if they imposed an “undue burden,” is another example. Moreover, providing clear answers to questions that trouble the lower courts is one of the Supreme Court’s major responsibilities. The federal appellate courts handle 35,000-40,000 cases annually, the Supreme Court only about seventy-five, and the Court’s failure to set out clear rules to guide those courts has cost much time and money.

Should the Democrats be in a position to appoint enough Justices to create a “perfectionist” majority on the Court, why should these Justices not abolish capital punishment once and for all, as courts in other countries have done? Why should they not provide gays and lesbians with the same degree of protection available to other minorities with a long history of discrimination? Overturn the ludicrous 1976 Buckley v. Valeo decision, which equates speech with money and frustrates any hope of meaningful campaign finance reform? Authorize physician-assisted suicide for terminally ill patients who are in terrible pain? Restore the protections for the right to an abortion that Casey undid? All these changes can be made within the limits of judicial prudence and principled adjudication. Right-wing judges have never worried about being wrong. Why should liberals?

That opportunity may not come for quite a while, however. Roberts is 51, Alito is 56, Thomas is 57 and Scalia and Kennedy are vigorous 70-year-olds. The four liberals range from 67 to 86. There will thus be few opportunities to achieve even a thin liberal majority. Some victories will still come, for it is not possible to turn the clock back completely, nor do most conservatives want to. Also, Kennedy may come to find the other four too extreme, as he has several times this year. And there may be surprises. But the odds are against any great advances and for some serious setbacks, at least in the near future. The only way the Supreme Court can be moved back to the left is through politics. As Senator Barack Obama told an Illinois audience after the Alito vote this past January, “If we don’t win elections, you’re not going to get the judges you want.” For that to happen, Democrats have to renew themselves as a party that offers Americans what they need, not just what the “have mores” want. It’s not clear that today’s Democrats are able–or willing–to do that.