President Bush today named appeals court Judge Samuel A. Alito Jr. to the U.S. Supreme Court. Alito, 55, serves on the Philadelphia-based U.S. Court of Appeals for the Third Circuit, where his record on abortion rights and church-state issues has been widely applauded by conservatives and criticized by liberals.

Alito, appointed to the appeals court in 1990 by President George H.W. Bush, has been a regular for years on the White House's short list for the high court. He was also among those proposed by conservative intellectuals as an alternative to Harriet Miers, the White House counsel who withdrew as the nominee last week.

"Judge Alito has gained the respect of his colleagues and attorneys for his brilliance and decency," Bush said in making his announcement at 8 a.m. today. "He's won admirers across the political spectrum. I'm confident that the United States Senate will be impressed by Judge Alito's distinguished record, his measured judicial temperament, and his tremendous personal integrity."

Alito thanked Bush and said that if confirmed by the Senate he would work to "interpret the Constitution and the laws faithfully and fairly, to protect the constitutional rights of all Americans, and to do these things with care and with restraint, always keeping in mind the limited role that the courts play in our constitutional system."

But the nomination immediately raised strong concerns among liberals. Some Democrats, including Senate Minority Leader Harry M. Reid (D-Nev.), have threatened to oppose Alito's confirmation. Immediately after the announcement, the liberal activist organization People for the American Way announced the launch of a "massive national effort" to prevent Alito's confirmation.

A major battle seemed inevitable in the Senate as a number of civil rights and women's rights groups vowed by midday to defeat the nomination, declaring that they will not allow a conservative on such social issues to take the seat of moderate Justice Sandra Day O'Connor. Conservative organizations, with equal vigor, geared up in support.

Alito is Bush's second choice in a month for the seat being vacated by O'Connor, who has announced her retirement but has remained on the court pending confirmation of a successor.

Alito noted his pleasure at being selected to replace O'Connor, saying, "I argued my first case before the Supreme Court in 1982, and I still vividly recall that day. I remember the sense of awe that I felt when I stepped up to the lectern. And I also remember the relief that I felt when Justice O'Connor -- sensing, I think, that I was a rookie -- made sure that the first question that I was asked was a kind one. I was grateful to her on that happy occasion, and I am particularly honored to be nominated for her seat."

Bush, fresh from withering criticism of Miers for her lack of judicial experience and questions about her intellect, stressed Alito's many years of litigation experience, first arguing 12 cases before the Supreme Court and then his years as an appeals court judge. Bush said Alito was the most experienced nominee in 70 years. The president highlighted the fact that Alito went to the Yale Law School, where he was an editor of the prestigious law review.

Alito's resume, including his service in the Justice Department during the Reagan administration, is very much unlike that of Miers's, who had no appellate experience, and very much like that of Chief Justice John G. Roberts Jr.

And like Roberts, Alito served during the Reagan administration in the Office of the Solicitor General, which argues on behalf of the government before the Supreme Court.

Unlike Roberts, he has opined from the bench on abortion rights, church-state separation and gender discrimination to the pleasure of conservatives and displeasure of liberals.

While he has been dubbed "Scalito" by some lawyers for a supposed affinity to conservative Supreme Court Justice Antonin Scalia and his Italian-American heritage, most observers believe that greatly oversimplifies his record.

Alito is considered far less provocative a figure than Scalia both in personality and judicial temperament. His opinions and dissents tend to be dryly analytical rather than slashing.

In addition, his appeals court record is not uniformly conservative on the sorts of issues that arise in Supreme Court confirmation battles.

In 2004, he ruled in favor | of a complaint brought under the Individuals with Disabilities Education Act by a boy badly bullied by his classmates who was seeking legal relief but had been rebuffed by a U.S. District Court.

He also authored a majority opinion | granting federal court review to an African American who could not get state courts to hear his claim of racial bias on the part of a juror in his trial. The case involved a juror who used racial epithets outside the confines of the jury room.

His record on the appeals court makes Alito less liable to suggestions made about Roberts, with only two years as a judge, that he is somehow a judicial mystery.

Rather, liberals are likely to focus on his opinions and dissents, most notably in the 1991 case, Planned Parenthood v. Casey.

In that case, Alito joined a Third Circuit panel in upholding most of a Pennsylvania law imposing numerous restrictions on women seeking abortions. The law, among other things, required physicians to advise women of the potential medical dangers of abortion and tell them of the alternatives available. It also imposed a 24-hour waiting period for abortions and barred minors from obtaining abortions without parental consent.

The panel, in that same ruling, struck down a single provision in the law requiring women to notify their husbands before they obtained an abortion. Alito dissented from that part of the decision.

Citing previous opinions of O'Connor, Alito wrote that an abortion regulation is unconstitutional only if it imposes an undue burden on a woman's access to the procedure. The spousal notification provision, he wrote, does not constitute such a burden and must therefore only meet the requirement that it be rationally related to some legitimate government purpose.

"Even assuming that the rational relationship test is more demanding in the present context than in most equal protection cases, that test is satisfied here," he wrote.

"The Pennsylvania legislature could have rationally believed that some married women are initially inclined to obtain an abortion without their husbands' knowledge because of perceived problems -- such as economic constraints, future plans, or the husbands' previously expressed opposition -- that may be obviated by discussion prior to the abortion.

"In addition," he wrote, "the legislature could have reasonably concluded that Section 3209 [the spousal provision] would lead to such discussion and thereby properly further a husband's interests in the fetus in a sufficient percentage of the affected cases to justify enactment of this measure. . . . The Pennsylvania legislature presumably decided that the law on balance would be beneficial. We have no authority to overrule that legislative judgment even if we deem it "unwise" or worse."

The case ultimately reached the Supreme Court, which upheld the appeals court decision, disagreed with Alito and used the case to reaffirm its support for Roe v. Wade, the 1973 decision legalizing abortion.

On the spousal notification provision, O'Connor wrote for the court that it did indeed constitute an obstacle. The "spousal notification requirement is . . . likely to prevent a significant number of women from obtaining an abortion," she wrote.

"It does not merely make abortions a little more difficult or expensive to obtain; for many women, it will impose a substantial obstacle. We must not blind ourselves to the fact that the significant number of women who fear for their safety and the safety of their children are likely to be deterred from procuring an abortion as surely as if the Commonwealth had outlawed abortion in all cases," she said.

Plus, it "embodies a view of marriage consonant with the common law status of married women, but repugnant to our present understanding of marriage and of the nature of the rights secured by the Constitution. Women do not lose their constitutionally protected liberty when they marry, " she said.

"The Constitution protects all individuals, male or female, married or unmarried, from the abuse of governmental power, even where that power is employed for the supposed benefit of a member of the individual's family."

While lauded by conservatives, Alito has also been criticized by women's rights organizations for his 1996 dissent in a sex discrimination case, Sheridan v. Dupont, in which he argued that the Third Circuit had made it too easy for discrimination complaints to reach a jury trial. The standards for deciding when a discrimination case reaches trial are hotly controversial as they determine whether such a case moves forward at all.

The dissent | ended a significant dispute in the circuit over the analytical framework for granting summary judgments dismissing a complaint without a trial under Title VII of the Civil Rights Act of 1964.

Alito initially challenged the existing framework and prevailed when the case was before a three-judge panel. He lost the battle when the full circuit ruled.

The widely discussed exchange in the Sheridan case illustrated both Alito's willingness to take on a potentially losing battle in the law and his approach to such battles, which, in that case, was calm, analytical and devoid of flamboyant rhetoric.

In the area of church and state, Alito has been consistently supportive of the conservative view that the courts should be more accommodating when considering state entanglement with religion. He wrote a majority opinion in ACLU v. Schundler |, holding that a city's holiday display that included a creche and menorah did not violate the establishment clause of the First Amendment because it included secular symbols as well, such as Frosty the Snowman.