The Supreme Court said in a press release that Barrett will be able to start her new role after Chief Justice John Roberts administers her judicial oath on Tuesday. Justice Clarence Thomas administered the constitutional oath at Monday's ceremony.
Thomas has long been considered one of the more conservative justices on the court, along with Barrett's mentor, the late Justice Antonin Scalia. Echoing her mentor, Barrett underscored the need for a separation of powers between the judicial and legislative branches.
"It is the job of a senator to pursue her policy preferences," Barrett said to an audience on the South Lawn of the White House. "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."
The separation of duty is what makes the judiciary distinct, she said.
"A judge declares independence not only from Congress and the president, but also from the private beliefs that might otherwise move her," she said.
The Senate confirmed Barrett with a 52-48 vote. All 45 Democrats and two independents who caucus with the Democrats opposed her confirmation.
Controversial from the start, her confirmation prompted a wave of backlash on Monday. Almost immediately after the Senate voted, Democratic lawmakers panned the decision while some called demanded leaders "expand the court."
Barrett's confirmation solidified a conservative majority on the nation's highest court, and gave Trump another victory as he headed into election day.
Whoever wins on Nov. 3 will likely have major consequences on the Supreme Court as an American institution. Former Vice President Joe Biden has mostly refused to answer questions about whether he would pack the courts.
On Monday, Biden said that he might be open to shifting Supreme Court justices to lower courts if elected president, noting that he hadn't made any judgment yet on the issue.
“There is some literature among constitutional scholars about the possibility of going from one court to another court, not just always staying the whole time in the Supreme Court but I have made no judgment," Biden said at a campaign stop in Chester, Pa.
He went on to say that "there are just a group of serious constitutional scholars, have a number of ideas how we should proceed from this point on."
"That's what we're going to be doing. We're going to give them 180 days God-willing if I'm elected, from the time I'm sworn in to be able to make such a recommendation."
During an interview with "60 Minutes," Biden said he would set up a commission that would make recommendations for reforming the court system.
"I will ask them to, over 180 days, come back to me with recommendations as to how to reform the court system because it's getting out of whack," he said.
Fox News' Tyler Olson contributed to this report.