U.S. Appeals Court Judge Brett M. Kavanaugh, President Trump’s Supreme Court nominee, will begin to face his Senate confirmation fight on Tuesday. (Michael Reynolds/EPA-EFE/Shutterstock)

Two factors animate U.S. Appeals Court Judge Brett M. Kavanaugh’s crucial Supreme Court confirmation hearings that begin Tuesday in the Senate: one is the justice he would succeed, and the other is the president who chose him.

A host of issues are at stake with the departure of the court’s pivotal justice, Anthony M. Kennedy, whose swing-vote jurisprudence did not fit neatly into a conservative or liberal box. Abortion, affirmative action, the interplay of religious beliefs and gay rights, and the government’s protection of the environment are among the issues affected by Kennedy’s departure, and Kavanaugh is likely to be to the right of Kennedy on all.

But this confirmation fight also comes as the powers of a special prosecutor to investigate President Trump are part of a national debate, with important constitutional decisions on executive power and prerogative possibly awaiting the high court.

The politics of the Trump age only add to the battle over a judge whose lifetime appointment could seal a consistently right-leaning majority that the conservative legal movement has long labored to establish.

“This is an appointment that almost certainly will change the ideological makeup of the court in a meaningful way,” said Lori A. Ringhand, a University of Georgia law professor with an expertise in Supreme Court confirmation hearings.

Kavanaugh, 53, has a unique perspective on the issue of investigating the president. He spent years working for Kenneth Starr on the probe of President Bill Clinton, taking a hard line on what he termed Clinton’s lies and “pattern of revolting behavior” in connection with Clinton’s relationship with a White House intern. But Kavanaugh has since written that he believes a president should not be distracted by civil suits and criminal investigations while in office.

If Kavanaugh’s view is nuanced — he’s never said the Constitution prohibits such investigations — reaction from Democrats has been simple enough to fit in a tweet. Such as this one by Sen. Kamala D. Harris, the Democrat from California who will be among those on the Senate Judiciary Committee questioning Kavanaugh:

“The president is an unindicted co-conspirator in federal crimes and he has nominated someone to the Supreme Court who believes a sitting president should never be indicted.”

Kavanaugh’s Ivy League credentials, his outgoing personality, his close ties to the conservative legal establishment and his voluminous string of opinions and law review articles have long made him a likely choice for the Supreme Court under a Republican president.

“I don’t see him as remotely controversial,” said Lisa S. Blatt, a Washington lawyer who regularly argues before the Supreme Court and considers Kavanaugh a friend. “He’s such an obvious, conventional choice for a conservative. If Jeb Bush were president, he would have picked [Kavanaugh] before Neil Gorsuch.”

Blatt is a liberal Democrat, and has taken heat from progressives for her endorsement of Kavanaugh and her plans to introduce him Tuesday to the committee, along with former secretary of state Condoleezza Rice and Republican Sen. Rob Portman (Ohio).

At this point, it appears more likely that a handful of Democratic senators will cross over to support Kavanaugh than any Republicans will desert him. And just as with Trump’s first nominee — now Justice Neil M. Gorsuch — all Kavanaugh needs to become the nation’s 114th Supreme Court justice are the votes of Republican senators who make up the majority.

“I’ve been on the Judiciary Committee for the last fourteen Supreme Court confirmation hearings,” Sen. Orrin G. Hatch (R-Utah) said in a speech last week. “Judge Kavanaugh’s will be my fifteenth and final. He is as qualified and as ready to serve as any nominee I have seen to our nation’s highest court.”

The American Bar Association, which conservatives accuse of having a liberal bias, said Friday that Kavanaugh received a unanimous rating of “well qualified” from its screening committee, the highest ranking.

Democrats are far from over Republican efforts that denied President Barack Obama’s nominee Merrick Garland even a hearing in what would have been an appointment that would have moved the court in a different direction.

Obama nominated Garland — like Kavanaugh, a judge on the U.S. Court of Appeals for the District of Columbia Circuit — to fill the spot of the late justice Antonin Scalia, a conservative stalwart. Senate Majority Leader Mitch McConnell (R-Ky.) refused to consider the nomination until after the election, and his gamble paid off with Trump’s victory.

Liberal interest groups and Democrats also object to Kavanaugh’s nomination on both process and substance.

Only a portion of records amassed from Kavanaugh’s more than five years in President George W. Bush’s White House, as staff secretary, have been requested by Senate Republicans, and even those are being screened by Bush’s lawyer, who represents, among others, White House counsel Donald McGahn.

Beyond that, Kavanaugh’s opponents say the importance of replacing the court’s pivotal justice requires an examination of not just credentials but judicial philosophy and ideology.

Kennedy, chosen by President Ronald Reagan three decades ago, voted with conservatives about two-thirds of the time. But in the court’s most recent examination of state efforts to restrict abortion, as well as universities’ use of affirmative action in student admissions, Kennedy sided with liberals.

He wrote the court’s 5-to-4 decision that said gay couples have a constitutional right to be married.

As is usually the case at confirmation hearings, the abortion issue is likely to receive the most attention.

Republican senators Susan Collins (Maine) and Lisa Murkowski (Alaska) have said they will not support a nominee who would overturn abortion rights established by the court’s 1973 decision in Roe v. Wade.

After meeting with Kavanaugh, Collins said he told her he considered Roe “settled law,” just as Chief Justice John G. Roberts Jr. had at his confirmation hearing.

But that meant little to abortion rights supporters.

While there has not been a recent Supreme Court case directly challenging Roe or the other court precedents affirming the right to abortion, the chief justice and fellow George W. Bush nominee Justice Samuel A. Alito Jr. have been reliable votes for abortion restrictions in the most important cases to come before the court in their tenure.

Abortion rights supporters and those opposed expect Kavanaugh would be a justice in the same vein, forming a majority with fellow conservatives Gorsuch and Justice Clarence Thomas that would make it more difficult for a woman to obtain the procedure.

Kavanaugh has praised the late chief justice William H. Rehnquist and noted his dissent in Roe. He wrote a high-profile dissent when his court agreed that a undocumented teenage immigrant in government custody should be allowed to obtain an abortion.

“On the vital issues of protecting religious liberty and enforcing restrictions on abortion, no court-of-appeals judge in the nation has a stronger, more consistent record than Judge Brett Kavanaugh,” former law clerk Sarah E. Pitlyk, now special counsel for the Thomas More Society, wrote in the National Review.

Beyond Kavanaugh’s judicial opinions, Democrats will press his views on past writings and comments that could have a bearing on special counsel Robert S. Mueller III’s investigation of the Trump administration and Russian interference in the 2016 election.

He is sure to get questions on doubts he once expressed about the wisdom of the 1974 Supreme Court decision forcing President Richard M. Nixon to turn over secret White House tapes, and reservations Kavanaugh expressed about whether a sitting president should be protected from civil suits and criminal investigations.

Twenty years ago, at a lawyers’ roundtable discussion, Kavanaugh questioned the court’s decision in United States v. Nixon.

“Maybe Nixon was wrongly decided — heresy though it is to say so,” Kavanaugh said, adding “Maybe the tension of the time led to an erroneous decision.”

But in a 2016 speech, he listed the decision with several others when he said that “some of the greatest moments in American judicial history have been when judges stood up to the other branches, were not cowed, and enforced the law.”

The latter view is the one he has stressed in private meetings with senators.

As legal questions have arisen about whether Trump could be indicted while in office or forced to comply with a subpoena by Mueller, the Supreme Court could play a vital role.

In a 2009 Minnesota Law Review article, Kavanaugh said he had concluded that a president is too busy to be distracted by civil suits and criminal investigation while in office. Impeachment is the proper remedy for a president’s wrongdoing, Kavanaugh said, and Congress should protect the chief executive from other investigations until he leaves office.

“Your previous statements give me serious pause: an expansive view of presidential power held by a Supreme Court Justice occupying Justice Kennedy’s seat would undoubtedly mark a significant shift from our historical understandings and Supreme Court jurisprudence recognizing constitutional limits on the executive,” Sen. Christopher A. Coons (D-Del.) wrote to Kavanaugh in a letter Coons’s office released last week.

But others who have analyzed Kavanaugh’s writings say they are not out of the mainstream. For instance, the Justice Department for years has held the position that the president cannot be indicted.

And they say that Kavanaugh’s suggestion that Congress protect the president from investigations shows that he has not made up his mind that there is already a legal bar to such probes.