Jackson is the first black woman to serve on the Supreme Court.
Justice Stephen Breyer, who had served on the Supreme Court for almost 28 years, resigned at noon.
President Joe Biden nominated Jackson for the Supreme Court after Justice Stephen Breyer said he would step down at the end of the court's term.
Jackson was sworn in at the Supreme Court building in Washington. Jackson solemnly swore to defend the Constitution against all enemies, foreign and domestic, and tobear true faith and loyalty to the same.
Jackson swore to "administer justice without respect to persons, and do equal right to the poor and the rich."
Jackson, her husband, and their two daughters were present at the ceremony.
The investiture ceremony will take place in the fall. Jackson is the newest member of the high court.
Jackson was confirmed by the Senate in April with a vote of 53-47. She was confirmed by three Republican senators.
Jackson is thought to be a liberal judge. She is a member of the court along with two other liberals.
U.S. Supreme Court nominee Judge Ketanji Brown Jackson meets with U.S. Senator Tammy Baldwin (D-WI) (not pictured), on Capitol Hill in Washington, March 28, 2022.There is a supermajority of six conservatives on the Supreme Court, including Chief Justice John Roberts.
Clarence Thomas is the only black justice on the court. Thurgood Marshall was the first black person to serve on the court.
Public confidence in the Supreme Court has sunk to historic lows after a draft opinion on abortion was leaked.
According to a Gallup poll, only 25% of Americans have a lot of confidence in the court.
The level of confidence is 11 percentage points lower than it was a year ago and 5 percentage points lower than it was a year ago.
There is no federal constitutional right to abortion according to the Supreme Court.
The new ruling allows individual states to set their own restrictions on abortion without fear that they will run afoul of the Supreme Court's decision in 1973.
The votes needed to overturn the decision were provided by the appointees of the president.