President Bush is cementing Ronald Reagan's conservative transformation of the federal courts in the biggest turnover of federal judges since the New Deal of Franklin D. Roosevelt, according to academic and partisan monitors of the courts.

Two years into his presidency, and without the fierce nomination battles that became almost commonplace during the Reagan administration, Bush has appointed 70 judges. With vacancies -- as well as the creation of 85 judgeships by Congress late last year -- he has 134 more slots to fill. Reagan named 375 judges, about half the federal judiciary.

When the openings are filled, Reagan and Bush judges will account for nearly 70 percent of the federal judiciary -- an impact equaled only by Roosevelt, who appointed 75 percent of federal judges. Only three of the 13 federal appeals courts do not yet have a majority of judges nominated by Reagan and Bush.

Conservatives and liberals agree that the judges being picked by Bush are generally in the Reagan mold: conservatives who are committed to a narrow reading of the Constitution; are tough on crime; and view the judiciary as a vehicle for resolving discrete disputes, not an engine for social change.

Federal judges have the final word on such constitutional issues as abortion, religious freedom, affirmative action and the rights of criminal defendants. When Congress enacts a statute -- whether the new Americans with Disabilities Act or part of the federal bankruptcy code -- questions about how the law applies in practice end up in the hands of federal judges.

Because of this sweeping power, selection of conservative judges was a cornerstone of the Reagan administration. During the 1988 campaign, Bush vowed repeatedly to follow Reagan and appoint judges who would "interpret the law, not legislate from the bench."

"My sense is that it is very consistent with the Reagan mold," Murray G. Dickman, a top aide to Attorney General Dick Thornburgh, said of the selection process.

Conservatives, upset with Bush on a variety of other fronts, say they are delighted. "There is no area in which conservatives are more happy with George Bush than in judicial nominations," said Clint Bolick, director of the conservative Landmark Center for Civil Rights.

On one level, Bush's performance can be viewed as simply fulfilling a campaign promise. But as Thomas Jipping of the Free Congress Foundation noted, that was not a foregone conclusion.

"As conservatives saw in more and more policy areas -- everything from the 'no new taxes' thing on down -- compromises . . . we were sort of sitting there thinking, 'I wonder if the judicial selection process will be next,' " said Jipping. Instead, he said, "Judicial selection is one of the few areas where conservatives feel that he has still been consistent from the start."

Bush's nominees to the influential courts of appeals, he said, "are as good as or better on the whole than Ronald Reagan's. . . . They are judges whose judicial philosophies are devoted to the law rather than political factors."

University of Kansas political science professor C.K. Rowland, who has done extensive studies of judicial voting patterns, said it is too soon to measure the performance of Bush's judges. But he and other scholars agreed that a conservative judiciary is one of Reagan's most influential legacies.

Rowland's studies indicate that Reagan judges were far more likely than those appointed by President Jimmy Carter to rule against those claiming race discrimination and to throw out lawsuits by environmental, civil rights and other groups on the grounds that they lacked standing to sue.

Reagan judges sided with criminal defendants half as often (24 percent of cases) as Carter judges (47 percent of cases). And in the area of abortion rights, Rowland found "dramatic" differences between Reagan district judges and those named by Carter or his predecessors Richard M. Nixon and Lyndon B. Johnson -- with Reagan's judges "much more resistant to abortion rights."

Liberals, who had hoped Bush would select more moderate judges than Reagan, are as unhappy as conservatives are pleased. "Bush is quietly but as relentlessly using the courts to place those who are in sync with his ideology on civil rights and civil liberties issues and I think he's going at it with the same energy that Ronald Reagan did," said Nan Aron of the liberal Alliance for Justice.

The Reagan and Bush judiciaries look alike in a literal sense as well: overwhelmingly white, male and wealthy. Of Bush's nominees, 11.7 percent are female, compared to 8.2 percent of Reagan's selections and 15.5 percent of Carter's. Five, or 6.5 percent, are minorities, compared to 6 percent of Reagan's appointments and 21.3 percent of Carter's.

Dickman defended the administration's record, pointing out that the percentage of women and minorities named to the federal bench is as high or higher than in the general population of lawyers.

The continuity between the Reagan and Bush administrations is most apparent -- and most critical -- at the appeals court level, academic and partisan observers said. The appeals courts are, in effect, the courts of last resort for all but the relative handful of cases accepted for Supreme Court review. Bush has named 22 federal appeals court judges and has 22 vacancies to fill. He and Reagan will have appointed about 120 of the 179 circuit judges.

On the appeals court based in Philadelphia, for example, nine of the 10 active judges were named by Reagan or Bush; one lone Carter appointee remains. With the additional judgeships created by Congress just before it adjourned last year, Bush has another four nominations to make to that court.

In making such choices, Bush turns frequently to Reagan's slate of district judges. More than half the 23 appeals court selections so far (one nomination is pending) have been of district court judges appointed during the Reagan administration (11) or Reagan administration officials (3). Three nominees were initially tapped by Reagan but not confirmed before he left office.

Bush's three appointments to the federal appeals court here are illustrative of the trend: Clarence Thomas, Equal Employment Opportunity Commission chairman under Reagan; Karen L. Henderson, named by Reagan to the federal district court in South Carolina; and A. Raymond Randolph, a lawyer in private practice here and ally of former appeals court judge Robert H. Bork during his failed Supreme Court nomination.

In filling circuit court vacancies, Dickman said, the administration looks first to the pool of Reagan-appointed district judges. "These people essentially have become, if you will, the farm team for the circuits," he said, noting that choosing sitting judges, who have already had a body of opinions, gives the administration valuable clues about "their views and their predictability."

But there are also subtle differences between the Reagan and Bush appeals court nominees. Most noticeable is the absence of the conservative academics.

One explanation offered by observers of various political persuasions for the difference is that Reagan had already raided the law schools of many, if not most, of the academics who shared his conservative judicial philosophy.

But they suggested that the absence of academics may also underscore the lingering effect of the bruising nomination fights Reagan endured, not only over Supreme Court nominees such as Bork but on appeals court appointments such as University of San Diego law professor Bernard A. Siegan, an associate of then-Attorney General Edwin Meese III, whose nomination was rejected by the Senate Judiciary Committee in 1988.

After the Democrats regained control of the Senate in 1986 and successfully targeted Bork and, later, Siegan, observers suggested, Reagan's nominations generally became less confrontational; during his last two years in office, for example, Reagan turned increasingly to elevating sitting judges.

Bush, it appears, is continuing the later, more cautious, Reagan pattern. "As a general rule, I believe they have avoided red flag nominations," said Sheldon Goldman, a political science professor at the University of Massachusetts who has studied Reagan and Bush judicial nominations.

Dickman said, however, "We're not going to duck fights if we think there are appropriate candidates," and a major battle is brewing over one nominee, U.S. District Judge Kenneth L. Ryskamp of Miami.

Tapped for the 11th Circuit, one of the few not yet dominated by Reagan-Bush appointees, Ryskamp has been targeted for defeat by liberals who complain about his rulings against plaintiffs in civil rights cases, his membership in an allegedly discriminatory country club and what they view as insensitive comments from the bench.

But as a general matter, said Melanne Verveer of People for the American Way, which fought many Reagan nominations and opposes Ryskamp, "Certainly they've lowered the contention over nominees."

Some conservative activists say the difference also reflects the two presidents' approaches. "In the balance between conservatism and confirmability in a post-1987, post-Bork era, Bush tends more to confirmability, and Reagan, if he were president right now, might have tended more toward conservatism," Jipping said.

Goldman, who has conducted extensive studies of the backgrounds of Reagan and Bush judges, said he thought it was "a safe bet to say that, on the whole, the {Bush} group will be roughly as conservative as the Reagan group."

Pointing to the high proportion of Reagan district court judges promoted by Bush to the appeals courts, he said, "If they were conservative by Reagan standards, I would be incredulous if they somehow became flaming moderates on the circuit courts of appeals."