The Supreme Court welcomes its newest justice Tuesday as Brett Kavanaugh takes the bench for his first arguments since a contentious Senate voted narrowly to confirm him, cementing a decades-long campaign by conservatives to reshape the nation's highest court.

On Monday evening Kavanaugh, 53, joined family members, friends and President Trump at the White House for a ceremonial swearing-in ceremony, where the new justice tried to ease the partisan wounds from his confirmation process.

"The Supreme Court is an institution of law. It is not a partisan or political institution," Kavanaugh said. "The justices do not sit on opposite sides of an aisle. We do not caucus in separate rooms. The Supreme Court is a team of nine, and I will always be a team player on the team of nine."

President Trump, however, began the ceremony with a sharp partisan rebuke.

"On behalf of our nation, I want to apologize to Brett and the entire Kavanaugh family for the terrible pain and suffering you have been forced to endure," Trump said.

"A man or a woman must always be presumed innocent, unless or until proven guilty," the president added, to applause in the White House East Room. "And with that, I must state that, you sir, under historic scrutiny, were proven innocent."

Kavanaugh thanked some of the senators key to his confirmation, including Maine Republican Susan Collins and West Virginia Democrat Joe Manchin, who sealed the bare majority needed to confirm him.

"Although the Senate confirmation process tested me, as it has tested others, it did not change me," the justice said, affirming that he's committed to fairness and impartiality on the bench.

Kavanaugh is getting off to a swift start. He's already hired four women to serve as his Supreme Court clerks, something that he noted Monday evening was a first, and studied the legal briefs for the cases on deck. Those center on which kinds of crimes trigger mandatory prison terms under the Armed Career Criminal Act.

Any technical arguments are likely to be overshadowed by Kavanaugh's first public appearance wearing the traditional black robe donned by Supreme Court justices.

The bruising campaign to install Kavanaugh onto the court could leave a mark on his reputation and on public confidence in the institution, legal experts say.

The former dean of Yale Law School, from which Kavanaugh graduated, wrote he was "shell shocked" by the judge's forceful testimony denying sexual assault allegations and decrying what he called a concerted effort by liberal enemies, including the Clintons.

"For as long as Kavanaugh sits on the court, he will remain a symbol of partisan anger, a haunting reminder that behind the smiling face of judicial benevolence lies the force of an urgent will to power," Yale law professor Robert Post wrote in Politico. "No one who felt the force of that anger could possibly believe that Kavanaugh might actually be a detached and impartial judge."

Kavanaugh's allies predicted the partisan air around his confirmation would fade. They point out he served for 12 years on the country's second most important court, the U.S. Court of Appeals for the D.C. Circuit, where he penned more than 300 opinions, many of which were upheld by the Supreme Court.

"These things always blow over," Senate Majority Leader Mitch McConnell, R- Ky., said in a news conference shortly after Kavanaugh won confirmation.

The justices themselves have expressed concern in recent years about public perception of the court.

"This is a really divided time," said Justice Elena Kagan, who addressed the current climate of the court at an event at Princeton last week. "Part of the court's strength and part of the court's legitimacy depends on people not seeing the court in the way that people see the other governing structures in this country."

Chief Justice John Roberts has made keeping the court above the partisan fray a priority in his tenure.

Roberts addressed that issue in 2017, in remarks at Rensselaer Polytechnic Institute.

"It is a real danger that the partisan hostility that people see in the political branches will affect the nonpartisan activity of the judicial branch," he said. "It is very difficult I think for a member of the public to look at what goes on in confirmation hearings these days, which is a very sharp conflict in political terms between Democrats and Republicans, and not think that the person who comes out of that process must similarly share that partisan view of public issues and public life."

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