WASHINGTON - Under intense pressure at his nationally televised Senate hearing yesterday, Judge John G. Roberts Jr. never lost his cool and never gave an inch.

He was soft-spoken, even-tempered and smoothly evasive through a long day of questioning. Politely but resolutely, he refused to let senators bait him into offering his views on emotional legal issues while avoiding mistakes that might have impeded his smooth sail to confirmation as chief justice.

President Bush's first Supreme Court nominee presented himself as a moderate conservative, an old-fashioned judge who believes cases should be decided from bottom-up facts, rather than from an overarching, top-down ideology.

While revealing little about what he thinks or where he would like to lead the Supreme Court, Roberts surprised liberals and conservatives with some of his answers.

He readily acknowledged, for instance, that Americans have a right to privacy that grows out of various provisions of the Constitution, including the due process clause.

Change in thinking
That appeared to be a significant change in thinking for Roberts, who wrote dismissively, as a Reagan administration lawyer in 1981, of a "so-called right to privacy" not found in the Constitution.

Many conservatives have long disputed the notion of such a "right to privacy," described in rulings by the Warren court in the 1960s and forming the basis for the court's landmark abortion-rights decision in 1973.

Sen. Charles E. Schumer of New York, one of Roberts' biggest Democratic critics on the Judiciary Committee, told Roberts toward the end of the day that many senators had been "pleasantly surprised" by his testimony, including his remarks about privacy rights.

During more than eight hours of questioning, Roberts sketched a subtle self-portrait that appeared to be directed at liberals who have warned that he intends to move the judicial branch sharply to the right.

"Given my view of the role of a judge which focuses on appropriate modesty and humility, the notion of dramatic departures is not one that I would hold out much hope for," Roberts said, after Republican Sen. Lindsey Graham of South Carolina asked whether a Roberts court would be a significant departure from the conservative one led by Roberts' mentor, Chief Justice William H. Rehnquist, who died this month.

On abortion, the most contentious issue at the hearings and the basis for much of the opposition to his nomination, Roberts gave answers that surprised and worried some of his conservative backers.

Though he refused to discuss abortion cases, Roberts left the clear impression that he would be very hesitant to overrule Roe v. Wade, the 1973 abortion-rights decision, in the near future.

Elaborating on his testimony at his federal appeals court confirmation hearing two years ago, Roberts offered a textbook description of the importance of legal precedent, essentially describing the doctrine of abortion rights as a precedent that should not be easily overruled.

'Stability' stressed
"It is a jolt to the legal system when you overrule a precedent," Roberts said. He emphasized his belief in the importance of "stability" in the legal system.

The Supreme Court, he said, should consider overruling a precedent only after concluding that previous rulings on a subject had become unworkable and had been eroded by other Supreme Court rulings.

A 1992 Supreme Court decision in a Pennsylvania abortion case, which modified and reaffirmed Roe, was itself an important precedent in abortion law, he said.

By setting what appeared to be a high threshold for overruling Roe, Roberts left some of his most ardent conservative backers shaken.