As far as anyone yet knows, Judge Samuel A. Alito Jr. has not made any public declaration calling for the overruling of Roe v. Wade, the 1973 Supreme Court decision that recognized a constitutional right to abortion.

At least on the surface, Alito's record as an appeals court judge contains something for everyone. In 1991, he voted to uphold a Pennsylvania law that would have required married women to notify their husbands before getting an abortion. In 1995, however, he cast a deciding vote on a three-judge panel to strike down what abortion rights advocates saw as Pennsylvania's onerous regulations on federally funded abortions for victims of incest or rape. And in 2000, he concurred in a ruling that struck down a New Jersey ban on the late-term procedure called partial-birth abortion by opponents.

Yet for supporters and skeptics, Alito's record is not ambiguous, and it points toward the same conclusion: He would probably vote to strike down Roe. And they say this for a similar reason: It's not the results Alito reached in past cases that matters, it's his legal reasoning.

Alito's dissenting opinion in the 1991 case, which was later rejected by a 5 to 4 vote of the Supreme Court, shows "there was a little bit of interpretation, and more room for him to apply his own perspective to it," said Marcia Greenberger, co-president of the National Women's Law Center, which backs abortion rights. As a result, she said, his true anti-Roe colors came through.

As for Alito's vote to strike down Pennsylvania's rules on abortions funded by Medicaid, conservatives dismiss that as a ruling that turned on the finer points of administrative law. "It can't be characterized as an abortion ruling on the merits," said Jan LaRue, chief counsel of Concerned Women for America, which opposes Roe.

The abortion debate is at the heart of the incendiary politics surrounding Supreme Court nominations -- and those politics are heated largely because of Roe itself, which brought the court into an area that had previously been the province of state legislatures.

Strictly speaking, the Roe debate is not about whether abortion should be legal or illegal. The Roe decision struck down all state prohibitions on abortion, so overturning it would simply make it possible for states to ban abortion again -- but not mandatory that they do so.

In addition, replacing Justice Sandra Day O'Connor, who supports Roe, with an anti-Roe justice would not create a majority on the court for overturning Roe. Rather, the vote count would still be at least 5 to 4 in favor of the basic abortion right recognized in the decision because Justices John Paul Stevens, Anthony M. Kennedy, David H. Souter, Ruth Bader Ginsburg and Stephen G. Breyer support it.

Chief Justice John G. Roberts Jr. has yet to put his view on the record, though his otherwise conservative background suggests he would vote to overturn Roe.

In ruling on abortion-related issues that have come before him as a judge on the U.S. Court of Appeals for the 3rd Circuit, Alito was bound to follow Supreme Court precedent.

For that reason, abortion rights advocates tend to discount his ostensibly pro-abortion-rights rulings, saying that they reflect the fact that he was tightly constrained by higher legal authority.

In the 1995 case, Blackwell v. Knoll, the issue before a panel of three judges was how far Pennsylvania could go in regulating abortions paid for by Medicaid.

Congress had forbidden Medicaid from paying for abortions, except in cases of rape, incest or a danger to the life of the woman. Pennsylvania wanted proof that women had first reported the alleged rape or incest, or, in the case of a threat to a woman's life, a certification from a doctor other than the one about to perform the abortion.

Alito co-signed an opinion by Judge Robert E. Cowen holding that Pennsylvania's rules had to yield to a contrary federal policy, which said states must permit doctors to waive any such regulations if necessary. Cowen's opinion decided the case based on Supreme Court precedents requiring court deference to reasonable federal agency interpretations.

Alito's vote is "no surprise," Greenberger said. "He was operating within these broader constraints that apply to lower court judges and don't apply to a Supreme Court justice."

"There is no basis for inferring from this case anything about how Alito would approach other cases involving abortion," Edward Whelan, president of the conservative Ethics and Public Policy Center, wrote in a Web posting defending Alito's vote.

Conservatives make a similar point in discounting Alito's vote to strike down the New Jersey ban on some late-term abortions in 2000. The issue had just been decided by the Supreme Court, so the 3rd Circuit had little choice but to follow precedent.

Alito published an opinion chiding two judges of the court for publishing a long opinion, which they had prepared months earlier but held until the Supreme Court ruled.

Alito said it "was never necessary and is now obsolete," because of the Supreme Court's decision. Some abortion rights advocates say that remark shows that Alito's agreement in the decision was grudging, but conservatives say it merely shows "that he wanted to state that what the majority had written was pretty much moot at that point," as LaRue puts it.

It is Alito's concurring opinion in the 1991 case, Planned Parenthood v. Casey, that most intrigues supporters and opponents of Roe.

For abortion rights advocates, the opinion shows that, on the one occasion when the applicable Supreme Court precedent was not crystal clear, he tried to push the law to the right -- arguing that an ambiguous standard sketched by O'Connor could be stretched to permit a state law requiring married women to notify their husbands before getting an abortion, unless they could show a threat of imminent physical harm.

"He was interpreting that in the most constraining way he could, and it would have resulted in horrible consequences for women," said Priscilla Smith of the Center for Reproductive Rights, a New York-based nonprofit that supports abortion rights. She said Alito ignored the possibility that women with abusive husbands might have faced other threats such as psychological abuse or physical retaliation against their other children.

But backers of the judge say that, in deferring to what he considered reasonable policy judgments by the legislature, Alito was exhibiting judicial restraint.

"If you study that case, what you find is a judge doing his level best to discern the rule of law," said Charles J. Cooper, a Washington lawyer who supervised Alito when both men were officials in the Reagan administration Justice Department.

Despite the absence of a clear anti-Roe statement from Alito in that case or any other, Whelan said, "someone who's shown the high-quality judging Alito has and is not ideologically driven to the left will of course recognize that Roe is an abomination that has distorted American politics for 30 years."