Brett Kavanaugh was sworn in as the 114th justice of the US Supreme Court, after a wrenching debate over sexual misconduct and judicial temperament that shattered the Senate, captivated the nation and ushered in an acrimonious new level of polarization — now encroaching on the court that the 53-year-old judge may well swing rightward for decades to come.

Even as Kavanaugh took his oath of office Saturday evening in a quiet private ceremony, not long after the narrowest Senate confirmation in nearly a century and a half, protesters chanted outside the court building across the street from the Capitol.

The climactic 50-48 roll call capped a fight that seized the national conversation after claims emerged that he had sexually assaulted women three decades ago — allegations he emphatically denied. Those accusations transformed the clash from a routine struggle over judicial ideology into an angry jumble of questions about victims’ rights, the presumption of innocence and personal attacks on nominees.

His confirmation provides a defining accomplishment for President Donald Trump and the Republican Party, which found a unifying force in the cause of putting a new conservative majority on the court. Before the sexual accusations grabbed the Senate’s and the nation’s attention, Democrats had argued that Kavanaugh’s rulings and writings as an appeals court judge raised serious concerns about his views on abortion rights and a president’s right to bat away legal probes.

Trump, flying to Kansas for a political rally, flashed a thumbs-up gesture when the tally was announced and praised Kavanaugh for being “able to withstand this horrible, horrible attack by the Democrats.” He later telephoned his congratulations to the new justice, then at the rally returned to his own attack on the Democrats as “an angry left-wing mob.”

Like Trump, senators at the Capitol predicted voters would react strongly by defeating the other party’s candidates in next month’s congressional elections.

“It’s turned our base on fire,” declared Senate Republican leader Mitch McConnell of Kentucky. But Democratic leader Chuck Schumer of New York forecast gains for his party instead: “Change must come from where change in America always begins: the ballot box.”

The justices themselves made a quiet show of solidarity. Kavanaugh was sworn in by Chief Justice John Roberts and the man he’s replacing, retired Justice Anthony Kennedy, as fellow Justices Samuel Alito, Clarence Thomas, Ruth Bader Ginsburg and Elena Kagan looked on — two conservatives and two liberals.

Still, Kagan noted the night before that Kennedy has been “a person who found the center” and “it’s not so clear we’ll have that” now.

Noisy to the end, the Senate battle featured a call of the roll that was interrupted several times by protesters shouting in the spectators’ gallery before Capitol Police removed them. Vice President Mike Pence presided, his potential tie-breaking vote unnecessary.

Trump has now put his stamp on the court with his second justice in as many years. Yet Kavanaugh is joining under a cloud. Accusations from several women remain under scrutiny, and House Democrats have pledged further investigation if they win the majority in November.