However, the first of at least four days of hearings by the Senate Judiciary Committee began with partisan quarrelling over the nomination and persistent protests from members of the audience, followed by their arrests.

Strong Democratic opposition to Trump’s nominee reflects the political stakes for both parties in advance of the November elections, Robert Mueller’s investigation of Trump’s 2016 campaign and the potentially pivotal role Kavanaugh could play in moving the court to the right.

Democrats, including several senators poised for 2020 presidential bids, tried to block the proceedings in a dispute over Kavanaugh records withheld by the White House. Republicans in turn accused the Democrats of turning the hearing into a circus.

Trump jumped into the fray late in the day, saying on Twitter that Democrats were “looking to inflict pain and embarrassment” on Kavanaugh.

The president’s comment followed the statements of Democratic senators who warned that Trump was, in the words of Senator Richard Blumenthal of Connecticut, “selecting a justice on the Supreme Court who potentially will cast a decisive vote in his own case.”

In Kavanaugh’s own statement at the end of more than seven hours of arguing, the federal appeals judge spoke repeatedly about the importance of an independent judiciary and the need to keep the court above partisan politics, common refrains among Supreme Court nominees that had added salience in the fraught political atmosphere of the moment.

With his wife, two children and parents sitting behind him, Kavanaugh called himself a judge with a straightforward judicial philosophy.

“A judge must be independent and must interpret the law, not make the law. A judge must interpret statutes as written. A judge must interpret the Constitution as written, informed by history and tradition and precedent,” he said.

Kavanaugh also promised to be “a team player on the Team of Nine.”

The Supreme Court is often thought of as nine separate judges, rather than a team. And on the most contentious cases, the court tends to split into conservative and liberal sides. But justices often do say they seek consensus, and they like to focus on how frequently they reach unanimous decisions.

Barring a major surprise over the next two days of questioning, the committee is expected to vote along party lines to send Kavanaugh’s nomination to the full Senate.

Majority Republicans can confirm Kavanaugh without any Democratic votes, though they’ll have little margin for error.

“There are battles worth fighting, regardless of the outcome,” Democrat Senator Mazie Hirono said in an unsparing opening statement that criticised Kavanaugh’s judicial opinions and the Senate process that Democrats said had deprived them of access to records of important chunks of Kavanaugh’s time as an aide to President George W. Bush.

Democrats raised objections from the moment Chairman Chuck Grassley gavelled the committee to order. One by one, Democrats, including Kamala Harris of California, Cory Booker of New Jersey and Amy Klobuchar of Minnesota, all potential presidential contenders, demanded that Republicans delay the hearing. They railed against the unusual vetting process by Republicans that failed to include documents from three years Kavanaugh worked in the Bush administration, and 100,000 more pages withheld by the Trump White House. Some 42,000 pages were released on the evening before of the hearing.

“We cannot possibly move forward, Mr. Chairman, with this hearing,” said Harris at the top of proceedings. Grassley disagreed.

As protesters repeatedly interrupted the session, Republican Sen. Ted Cruz, who is fighting for his own re-election in Texas, apologised to Kavanaugh for the spectacle he said had less to do about the judge’s legal record than Trump in the White House.

“It is about politics,” said Cruz. “It is about Democratic senators re-litigating the 2016 election.”

The Republicans’ slim majority in the Senate was bolstered during the hearing by the announcement from Arizona that Governor Doug Ducey was appointing Jon Kyl, the former Republican senator, to fill the seat held by the late Senator John McCain. When Kyl is sworn in, Republicans will hold 51 of the 100 seats.

Senators Susan Collins of Maine and Lisa Murkowski of Alaska are the only two Republicans even remotely open to voting against Kavanaugh, though neither has said she would do so. Abortion rights supporters are trying to appeal to those senators, who both favour abortion access.

Kavanaugh sat silently and impassively for most of the day, occasionally sipping water and taking notes on senators’ points. Besides his family, he was accompanied by outgoing White House Counsel Don McGahn and Deputy Attorney General Rod Rosenstein.

Several dozen protesters, shouting one by one, disrupted the hearing at several points and were removed by police. “This is a mockery and a travesty of justice,” shouted one woman. “Cancel Brett Kavanaugh!” Others shouted against the president or to protect abortion access. “Senators, we need to stop this,” called out one.

As patience thinned and tempers flared, Republican Senator John Cornyn denounced what he called the “mob rule.” Struggling to speak over protesters, his fellow GOP Senator Orrin Hatch said: “These people are so out of line they shouldn’t be in the doggone room.”

But Democrat Senator Dick Durbin told Kavanaugh the opposition being shown at the hearing reflected the concern many Americans have over Trump’s “contempt of the rule of law” and the judge’s own expansive views on executive power.

“It’s that president who’s decided you are his man,” Durbin said. “Are people nervous about this concerned about this? Of course they are.”

The panel’s top Democrat, Senator Dianne Feinstein, described the hearing’s “very unique circumstances.”

“Not only is the country deeply divided politically, we also find ourselves with a president who faces his own serious problems,” she said referring to investigations surrounding Trump. “So it’s this backdrop that this nominee comes into.”