Following the Senate's confirmation of Judge Amy Coney Barrett to the Supreme Court, the White House hosted a ceremony where Justice Clarence Thomas administered the official constitutional oath to Barrett.
Supreme Court justices are required to take two oaths before they may execute the duties of their appointed office: the constitutional oath and the judicial oath.
Barrett will take the judicial oath on Tuesday in a private ceremony at the Supreme Court. Following that oath, she will officially become an active participant in court proceedings.
After taking the constitutional oath, Barrett used her brief remarks at the White House ceremony tonight to speak about the need for a federal judge to case aside her policy preferences in her decision-making.
"The confirmation process has made ever clearer to me one of the fundamental differences between the federal judiciary and the United States Senate. And perhaps the most acute is the role of policy preferences," Barrett said. "It is the job of a senator to pursue her policy preferences. In fact, it would be a dereliction of duty for her to put policy goals aside. By contrast, it is the job of a judge to resist her policy preferences. It would be a dereliction of duty for her to give into them. Federal judges don't stand for election. Thus, they have no basis for claiming that their preferences reflect those of the people. This separation of duty from political preference is what makes the judiciary distinct among the three branches of government."
As Barrett gets ready to join the court just one week before the election -- and Democrats fear she’ll intervene in any disputes arising from the vote -- Barrett added, “A judge declares independence not only from Congress and the president but also from the private beliefs that might otherwise move her.”
"The oath that I have solemnly taken tonight means at its core that I will do my job without any fear or favor, and that I will do so independently of both the political branches and of my own preferences," said said.
In his opening remarks, Trump called it a momentous day for America, the Constitution and the fair and impartial rule of law.
"The Constitution is the ultimate defense of American liberty, the faithful application of the law is the cornerstone of our republic. That is why as president I have no more solemn obligation of no greater honor than to appoint Supreme Court justices," President Donald Trump said at the beginning of the ceremony on the South Lawn.
"It is highly fitting that Justice Barrett fills the seat of a true pioneer for women, Justice Ruth Bader Ginsburg," Trump continued. "Tonight, Justice Barrett becomes not only the fifth woman to serve on our nation's highest court, but the very first mother of school-aged children to become a Supreme Court justice. Very important."
MORE: Senate Republicans poised to confirm Amy Coney Barrett to Supreme CourtFace coverings were required for all those attending, a senior White House official said in a statement, and the seated audience was socially distanced on the South Lawn. People "in close proximity" to the president were to be tested in advance.
The White House declined to comment on the number of attendees, but a pool report indicated there were about 200 chairs set up on the lawn.
Sen. Mike Lee, who tested positive six days after attending Barrett's Sept. 26 nominating event in the Rose Garden, attended Monday night's ceremony clad in a face mask. He was seen talking to national security adviser Robert O'Brien ahead of the event. O'Brien, also wearing a mask, tested positive for COVID-19 in July.
After the ceremony concluded, Barrett and Trump walked up to the South Portico and posed for cameras before being joined by their respective spouses. All were mask-less. The four of them, joined by a mask-less Thomas, proceeded into the White House.
The Senate floor vote began shortly before 8 p.m. and was completed in minutes. The vote was 52-48. Sen. Susan Collins, R-Maine, was the lone Republican to join the Democrats who unanimously voted against the confirmation. It was one of the narrowest Supreme Court confirmation votes in American history.
The count was the same as the confirmation vote for Thomas in 1991. Justice Brett Kavanaugh was confirmed by a vote of 50-48 in 2018. Ginsburg was confirmed 96-3 in 1993.
It's "the most conservative court in 100 years," Kate Shaw, Cardozo School of Law professor and ABC News Contributor, said on ABC News Live Prime.
At 48, Barrett becomes the youngest member of the court and will be there for generations. She's made history as the 115th justice -- and just the 5th woman to serve. She is the first mother of school-aged children and the only member of the court who did not graduate from the Ivy League.
On Sunday, senators voted along party lines to quash a Democratic filibuster of Barrett to replace the late liberal icon, Justice Ruth Bader Ginsburg. Collins, R-Maine, and Sen. Lisa Murkowski, R-Alaska, joined Democrats in the vote.
MORE: Reporter's Notebook: Sen. Murkowski on the 'incontrovertible' facts of Barrett voteMurkowski had initially opposed moving a nominee so close to the election, saying "fair is fair" given that her own party had blockaded President Barack Obama's pick in 2016 to replace the late Justice Antonin Scalia eight months before the election, but with Republicans securing the necessary votes for confirmation, Murkowski has changed course.
"While I oppose the process that has led us to this point," Murkowski said in a Saturday floor speech. "I do not hold it against her as an individual who has navigated the gauntlet with grace, skill and humility."
That move left Collins alone among the GOP opposition who voted against Barrett on Monday. Collins is in an extremely difficult fight for reelection in a moderate state where she has been lambasted for her past support of conservative jurists, including Trump's highly contentious nominee, Justice Brett Kavanaugh.
ABC News' John Santucci, Katherine Faulders and Lauren King contributed to this report.
This report was featured in the Tuesday, Oct. 27, 2020, episode of “Start Here,” ABC News’ daily news podcast.
"Start Here" offers a straightforward look at the day's top stories in 20 minutes. Listen for free every weekday on Apple Podcasts, Google Podcasts, Spotify, the ABC News app or wherever you get your podcasts.