In his opening remarks released ahead of delivery, Kavanaugh sought to tamp down the controversy over his nomination, which would likely shift the closely divided court to the right. He promised to be a "team player" if confirmed, declaring that he would be a "pro-law judge" who would not decide cases based on his personal views.
But Democrats raised objections from the moment Chairman Chuck Grassley gaveled the committee to order. They want to review 100,000 documents about Kavanaugh's record being withheld by the White House as well as some 42,000 documents released to the committee on a confidential basis on the eve of the hearing, along with others not sought by Republicans on the committee.
"We have not been given an opportunity to have a meaningful hearing on this nominee," said Sen. Kamala Harris, D-Calif. Sen. Richard Blumenthal, D-Conn., made a motion to adjourn.
Grassley denied his request, but the arguments persisted.
More than a 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!"
Grassley defended the document production as the most open in history, saying there was "no reason to delay the hearing. He asked Kavanaugh, who sat before the committee with White House officials behind him, to introduce his parents, wife and children.
"I'm very honored to be here," Kavanaugh said.
With majority Republicans appearing united, it's doubtful the hearings will affect the eventual confirmation of President Donald Trump's nominee. But they will likely become a rallying cry for both parties just two months before the midterm elections.
Kavanaugh declared he would be even-handed in his approach to the law.
"A good judge must be an umpire, a neutral and impartial arbiter who favors no litigant or policy," Kavanaugh said in prepared opening remarks. "I am not a pro-plaintiff or pro-defendant judge. I am not a pro-prosecution or pro-defense judge."
"I would always strive to be a team player on the Team of Nine," he added.
The Supreme Court is more often thought of as nine separate judges, rather than a team. And on the most contentious cases, the court tends to split into two sides, conservative and liberal. But the justices often say they seek consensus when they can, and they like to focus on how frequently they reach unanimous decisions.
Kavanaugh, 53, has served for the past 12 years on the federal appeals court in Washington, D.C., which is considered the second most important court in the country after the Supreme Court. His conservative record includes a dissenting opinion last year that would have denied immediate access to an abortion for an immigrant teenager in federal custody.
Kavanaugh worked in key White House positions when George W. Bush was president and was a member of independent counsel Kenneth Starr's legal team that investigated President Bill Clinton in the late 1990s, leading to Clinton's impeachment.
As a young lawyer, Kavanaugh worked for Justice Anthony Kennedy, whom he would replace on the high court. Kennedy retired at the end of July. Trump's successful first nominee, Neil Gorsuch, also was a Kennedy law clerk the same year as Kavanaugh.
When he was sworn in as an appellate judge in 2006, Kavanaugh called an independent judiciary "the crown jewel of our constitutional democracy."
Questioning of the nominee will begin on Wednesday, and votes in committee and on the Senate floor could occur later in September. If all goes as Republicans plan, Kavanaugh could be on the bench when the court begins its new term on Oct. 1.
Grassley has called Kavanaugh "one of the most qualified nominees ever picked for the court." The American Bar Association has given Kavanaugh its highest rating, well qualified.
Monday night, some 42,000 documents pertaining to Kavanaugh's work with previous administrations were released to the committee. Senate Democratic Leader Chuck Schumer complained it was impossible to go through them in time. Democrats have also complained that they have not received all relevant documents.
Rebuffed in their request to delay the hearing, Democrats are planning to shine a light on Kavanaugh's views on abortion, executive power and whether Trump could be forced to testify as part of special counsel Robert Mueller's Russia investigation.
Many Democratic senators already have announced their intention to vote against Kavanaugh and many Republicans have likewise signaled their support. A handful of Democrats seeking re-election in states Trump carried in 2016 could vote for Kavanaugh.
If no Democrat ultimately supports the nomination, the Republicans have no margin for error in a Senate they control by 50-49. Sens. 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 by focusing on concerns that Kavanaugh could vote to limit abortion rights or even overturn the landmark Roe v. Wade ruling from 1973 that first established a woman's constitutional right to an abortion.
Democrats have been under intense pressure from liberal voters to resist Trump, and many remain irate, even two years later, over the treatment of Merrick Garland, President Barack Obama's nominee for the Supreme Court, who was denied so much as a hearing last year by Majority Leader Mitch McConnell.
Kavanaugh, in his statement Tuesday, gave a shout-out to Garland, "our superb chief judge." Garland is the chief judge of the appeals court on which Kavanaugh has served.
But Democrats are powerless to delay a vote on Kavanaugh since McConnell led Republicans, during the Gorsuch nomination, in eliminating the 60-vote filibuster threshold that had been in place for Supreme Court nominations.
The filibuster rule required 60 of the 100 votes to advance a bill or nomination. That's in contrast to the simple 51-vote majority that applies in most cases.