Brown, Ketanji Jackson, a former public defender and Miami native who rose to become a judge on a powerful federal appeals court, became the first Black woman to serve on the Supreme Court on Thursday.

Jackson, a Harvard-educated lawyer who was confirmed by the Senate nearly three months ago, will take the seat previously held by Associate Justice Stephen Breyer. Breyer announced his retirement in January, making way for President Joe Biden to name Jackson as his first choice for the Supreme Court.

Jackson, a former judge on the powerful United States Court of Appeals for the District of Columbia Circuit, took the oath of office at a difficult time for the Supreme Court, as its decisions to overturn Roe v. Wade and expand access to handguns have exacerbated tensions among the justices and highlighted divisions among Americans over culture war issues.

But none of that was on display as Chief Justice John Roberts administered one oath of office to Jackson and Breyer – whom Jackson clerked for more than two decades – administered the other. As a result, Jackson became the court’s 104th associate justice, marking the first time that women and people of color outnumber white men.

In brief remarks, Roberts stated that the oaths allowed Jackson to carry out her duties “without further delay,” as she had been “anxious” to do.

When the justices reconvene in Washington in October, for the first time in the court’s 233-year history, there will be four women and two African Americans on the bench.

Jackson was confirmed by a vote of 53-47, with three Senate Republicans joining all Democrats in support. Jackson is not expected to change the court’s conservative bent because she is replacing Breyer, who was nominated by President Bill Clinton. Jackson, who is relatively young for a Supreme Court justice, could serve for decades.

Though Republicans generally praised Jackson’s demeanor, some accused her of being soft on crime and questioned her role in defending alleged terrorists who were designated as enemy combatants following the 9/11 attacks. Despite some harsh criticism – some of it unfair, according to Democrats – Jackson breezed through the hearings.

Jackson announced in March that she will recuse herself from a case pending before the Supreme Court challenging affirmative action policies at Harvard College and the University of North Carolina because she served on Harvard University’s board of overseers. Arguments in that appeal are scheduled for the fall.

Jackson will be the Supreme Court’s first former federal public defender. She will be the only justice who has served on the United States Sentencing Commission, a bipartisan body that makes recommendations about criminal sentences in federal court. Jackson will be one of two justices – along with Associate Justice Sonia Sotomayor – to have served as a trial court judge on a court where many of her colleagues worked in presidential administrations before becoming appeals court judges.

Conservatives criticized some of Jackson’s decisions, including one in 2019 in which she ruled that President Donald Trump’s former White House counsel, Don McGahn, had to testify as part of a congressional impeachment investigation. She was also chastised on the right for ruling against Trump’s plan to increase the number of illegal immigrants subject to expedited deportation.

Those same critics rarely mentioned other instances in which Jackson supported Trump, such as a legal challenge to his contentious border wall. In another case, she ruled that federal immigration law permitted faster removals of certain asylum seekers.

Jackson will join the court after a historic term in which tensions between the justices were exposed, a dramatic leak of a draft opinion in the abortion case undermined trust in the court’s protocols, and protests erupted in response to that leak, including some outside the homes of the justices themselves.

She has quietly observed those events in the months since her confirmation, leaving her in the unusual position of being a confirmed Supreme Court justice without an actual seat on the court. Breyer had always planned to retire at the end of his term, but his decision was made public in January, prompting Democrats with the smallest of Senate majorities to move quickly to confirm her.