With the U.S. Supreme Court building in the background, Supreme Court nominee Judge Brett M. Kavanaugh arrives prior to meeting with Senate Majority Leader Mitch McConnell (R-Ky.) on Tuesday on Capitol Hill in Washington. (Joshua Roberts/Reuters)

When Judge Brett M. Kavanaugh was nominated to the Supreme Court last week, he said he was “deeply honored” to have the chance to replace his old boss and the man he has called a mentor, Justice Anthony M. Kennedy.

But when Kavanaugh last September was asked to give a Constitution Day speech, he chose to celebrate his “first judicial hero,” the late Chief Justice William H. Rehnquist, noting Rehnquist’s dissent in Roe v. Wade and his rejection of the idea of a “wall of separation between church and state.”

Rehnquist was “not successful in convincing a majority of the justices in the context of abortion,” Kavanaugh told the American Enterprise Institute. But he said the man who served from 1972 to 2005, a conservative who during his tenure pushed the court to the right, was key in “limiting the court’s role in the realm of social policy and helping to ensure that the court operates more as a court of law and less as an institution of social policy.”

Liberal groups, abortion rights activists and antiabortion organizations all have seized on the speech, as well as Kavanaugh’s rulings involving a undocumented teenage immigrant seeking an abortion while in federal custody. Abortion will be a major topic at what are sure to be contentious confirmation hearings for the 53-year-old judge on the U.S. Court of Appeals for the D.C. Circuit.

But Kavanaugh’s speech, and other writings and talks he has given, underscore how different he is from Kennedy. President Trump has now nominated two former Kennedy clerks to the Supreme Court, and neither are in the mold of the retiring 81-year-old justice.

Both Kavanaugh and now-Justice Neil M. Gorsuch subscribe to an originalist interpretation of the Constitution associated with Justice Clarence Thomas and the late Justice Antonin Scalia, and clearly not with Kennedy.

As White House Counsel Donald McGahn told the Federalist Society after Gorsuch’s confirmation, “This administration’s mandate on judicial selections is crystal clear: Choose judges in the mold of Justice Scalia, Justice Thomas and now Justice Gorsuch.”

Of course, it would be almost impossible to select a justice in the mold of Kennedy. His unique views provoked equally distributed frustrations: disappointing conservatives by authoring Obergefell v. Hodges, which established a constitutional right for same-sex couples to marry, and outraging liberals with Citizens United v. FEC, which authorized unlimited campaign spending for businesses and other entities.

In one term, he was the only justice in both 5-to-4 majorities when he (and conservatives) removed a crucial part of the Voting Rights Act and when he (and liberals) overturned the federal Defense of Marriage Act, which denied recognition of same-sex marriages.

“There probably is not a single lawyer in the United States whose views align entirely with the justice’s, and there probably hasn’t been one for a while,” former Kennedy clerk Leah Litman wrote in a tribute to Kennedy on scotusblog.com.

In his speeches and writings, Kavanaugh is often noncommittal, describing in detail how different justices on the Supreme Court approach cases rather than offering what he thinks would be the best way.

But it is clear he would look to the approach employed by Scalia and Rehnquist. Kavanaugh thinks the Constitution affords the executive branch broad powers. At the same time, he would be far less likely than other judges to declare a law ambiguous and thus defer to an administration’s agency interpretations of regulations and implementation.

“Under the guise of ambiguity, agencies can stretch the meaning of statutes enacted by Congress to accommodate their preferred policy outcome,” he said in a tribute to Scalia at the University of Notre Dame.

Kavanaugh has spoken approvingly of the metaphor Chief Justice John G. Roberts Jr. used at his confirmation hearings of the judge as umpire. But there are no objective rules, he said, which frees some judges to impose their own views.

“It’s sometimes as if you were asked to umpire a baseball game, and you asked the commissioner of baseball whether the bottom of the strike zone was at the knees or at the hips, and you were told that it was up to you,” Kavanaugh said.

He also acknowledged that it was a difficult question as to when the Supreme Court should honor a precedent as settled law, or when it becomes important to overrule a wrongly decided case. “I wish I had the perfect answer,” he told one audience.

Kavanaugh was more forthcoming in the AEI speech, although he did not say explicitly that Rehnquist had been right to cast one of only two dissenting votes in the court’s 7-to-2 ruling that recognized a constitutional right to abortion.

But he did speak approvingly of Rehnquist’s reasoning. Because there is no stated right to abortion in the Constitution, Rehnquist said new “unenumerated” rights should be recognized only if they were “rooted in the traditions and conscience of our people.”

Abortion was not, he said.

The court considered overruling the decision in the 1992 case of Planned Parenthood v. Casey. Kennedy was on the court by then, and he was in the majority of the 5-to-4 vote to preserve abortion rights. Rehnquist again dissented.

In his speech, Kavanaugh did not mention Kennedy’s role in forming the Casey majority.

“It is fair to say that Justice Rehnquist was not successful in convincing a majority of justices in the context of abortion, either in Roe itself or in later cases such as Casey,” Kavanaugh said.

But Rehnquist did write the majority opinion when the court rejected the right to assisted suicide for the terminally ill.

“He was successful in stemming the general tide of freewheeling judicial creation of unenumerated rights that were not rooted in the nation’s history and tradition,” Kavanaugh said. That is the kind of criticism that has been aimed not only at the court’s decisions on abortion, but also gay rights.

Rehnquist was an associate justice before he became chief justice, and Kavanaugh said he began reading his opinions as a conservative first-year law student at liberal Yale Law School. Kennedy was still on the U.S. Court of Appeals for the 9th Circuit at the time.

Kavanaugh does not agree with all of Rehnquist’s opinions, he said, but as a young law school student in 1987, “his opinions made a lot of sense to me. In class after class, I stood with Rehnquist. That often meant in the Yale Law School environment of the time that I stood alone. Some things don’t change.”

In general, Kavanaugh described Rehnquist as having “righted the ship of constitutional jurisprudence” on the court in the period that followed Chief Justice Earl Warren’s tenure of sweeping change in areas such as racial discrimination, most notably to end segregation in public schools.

“The court, case after case, had seemed to be simply enshrining its policy views into the Constitution, or so the critics charged,” Kavanaugh said. “During Rehnquist’s tenure, the Supreme Court unquestionably changed and became more of an institution of law, where the court’s power is to interpret, and to apply the law [as] written, informed by historical practice, not by its own personal and policy predilections.”

Throughout the speech, Kavanaugh spoke approvingly of Rehnquist’s work, for instance, in reversing efforts to prevent religious institutions from receiving public money. Rehnquist was successful, Kavanaugh said, “in ensuring that religious schools and religious institutions could participate as equals in society and in state benefits programs.”

In another address, Kavanaugh touched on another topic that has new importance for him — the confirmation of federal judges.

Without referring explicitly to Senate Majority Leader Mitch McConnell’s refusal to allow a vote, or even a hearing, on President Barack Obama’s nominee to replace Scalia, Judge Merrick Garland, Kavanaugh noted he was on record as saying a president’s judicial nominee deserves a vote in the Senate within 180 days. (Kavanaugh also lavishly praised Garland.)

But asked whether the Senate should consider a nominee’s ideology when his confirmation could lead to overturning precedents of the departed justice, Kavanaugh declined to answer. Such a decision is up to the Senate, he said, and “above my pay grade.”

Correction: An earlier version of this story said Chief Justice William H. Rehnquist served on the Supreme Court starting in 1971. While he was nominated and confirmed that year, he joined the court in January 1972.