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Former Justice Sandra Day O’Connor, who blazed trails as the first woman to sit on the Supreme Court, has died, the court announced Friday morning.

O’Connor, 93, died due to “complications related to advanced dementia,” the court said.

O’Connor inspired generations of female lawyers – including the five women who served after her nomination on the high court. They admired her path marking success in a field that had been dominated by men. Over time, she became known as a moderate conservative and often the swing vote on hot-button social issues.

She died after living to see a new conservative-leaning court overturn an abortion decision she helped pen in 1992, lower the bar between church and state and set its sights on another area of interest to her: affirmative action.

Chief Justice John Roberts described O’Connor as a “patriot” and a “fiercely independent defender of the rule of law, and an eloquent advocate for civics education.”

President Joe Biden, meanwhile, hailed her as “an American icon.”

“I did not agree with all of her opinions, but I admired her decency and unwavering devotion to the facts, to our country, to active citizenship and the common good,” Biden said in a statement Saturday.

In 2018, O’Connor revealed in a letter that she had been diagnosed with the beginning stages of dementia, probably Alzheimer’s disease.

“While the final chapter of my life with dementia may be trying, nothing has diminished my gratitude and deep appreciation for the countless blessings of my life,” she wrote.

In nominating O’Connor for the bench in 1981, President Ronald Reagan called her “truly a person for all seasons, possessing those unique qualities of temperament, fairness, intellectual capacity, and devotion to the public good which have characterized the 101 brethren who have preceded her.”

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O’Connor sits with President Ronald Reagan in the Rose Garden of the White House on July 15, 1981. Reagan nominated O’Connor to the court earlier in July.

Growing up on the Lazy B Ranch in Arizona, O’Connor was known for her self-reliance and independence, traits she acquired as a young woman branding cattle, driving tractors, and firing rifles.

“She has shown time and time again that she is a true cowgirl,” the late Justice Ruth Bader Ginsburg said of O’Connor in a tribute in 2015.

O’Connor stepped down from the court in 2006 to care for her husband who was ailing from Alzheimer’s disease. President George W. Bush would go on to nominate Justice Samuel Alito to take her seat.

A graduate of Stanford University, she went on to study at Stanford Law School where she met and dated –for a time—her classmate the late Chief Justice William Rehnquist. She would go on to marry another classmate, John O’Connor.

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In this June 1982 photo, Supreme Court Justice Sandra Day O'Connor shakes hands at the graduation ceremonies at Stanford University. She gave the commencement speech that year.

Upon graduating, she was turned down by law firms because of her sex. Eventually, she started her own firm with her husband. Later, she served as an Arizona state senator as the first female majority leader. She was a judge of the Maricopa County Superior Court and, in 1979, the Arizona Court of Appeals.

“We all bring with us to the court or to any task we undertake our own lifetime of experiences and background,” O’Connor said in a 2003 CNN interview. “My perceptions might be different than some of my colleagues’ but at the end of the day we all ought to be able to agree on some sensible solution to the problem,” she said.

Former O’Connor clerk James Forman argued that her gender was not a factor in her jurisprudence.

“I don’t think there’s any decision you can say, ‘she reached this result because she’s a woman,’” Forman said.

Key vote on abortion, affirmative action, Bush v. Gore

During her tenure, the court for a time was known informally as the “O’Connor Court” because she served as the deciding vote in so many controversial cases. She was perhaps best noted for her vote in Planned Parenthood v. Casey, a 1992 opinion that reaffirmed a woman’s right to an abortion. Under the new ruling a state could not impose an “undue burden” on a woman seeking an abortion. The opinion would be overturned in 2022 by a conservative court bolstered by three of President Donald Trump’s nominees.

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Supreme Court Justice Sandra Day O'Connor in March 28, 1992.

O’Connor also wrote a 5-4 opinion upholding the University of Michigan Law School’s affirmative action program in 2003.

Nearly two decades later, the Supreme Court announced that it would take a fresh look at affirmative action during the 2022 term.

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She also penned the judgment of the court in 2004 ruling against the George W. Bush administration’s post-9/11 detainee policy, writing, “a state of war is not a blank check.”

She sided with the conservative side of the bench, however, in favor of Bush during the 2000 Bush v. Gore case that ensured the presidency for the Republican candidate and remained steadfast in supporting states’ rights.

While criticized at times for lacking a dedication to a hard and fast jurisprudential doctrine, she was known as a swing vote and a pragmatist who dealt with issues on a case-by case basis.

Former clerk Marci Hamilton said anyone who spoke of O’Connor being a fence-sitter was off-base.

“Those would be the people who have never met her,” Hamilton said. “Anyone who has met her knows that she makes up her own mind and is not at all concerned where anyone else is on the spectrum.”

Once she retired from the bench, her replacement, Alito, moved the court to the right on issues such as restrictions to abortion and campaign finance. It was Alito who would pen the 2022 decision overturning Roe v. Wade and Casey.

After leaving the high court and before her own diagnosis, O’Connor became an advocate for Alzheimer’s disease. She also launched a website dedicated to encouraging young people to learn civics.

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Sandra Day O'Connor does the pledge of allegiance while attending a citizenship hearing in Gilbert, Arizona, in 2005.
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O'Connor, right, was born March 26, 1930, in El Paso, Texas. Her parents were ranchers. Her mother, Ada Mae, is seen on the left holding Sandra's brother, Alan. Sandra's sister, Ann, is in the middle.
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O'Connor is seen second from left in the first row as she poses with other members of her Stanford Law School class in 1952. Another future Supreme Court justice, William Rehnquist, is in the back row on the far left.
MPI/Archive Photos/Getty Images
Upon graduating from law school, O'Connor was turned down by law firms because of her sex. Eventually, she started her own firm with her husband, John. Later, she served as an Arizona state senator as the first female majority leader. She was a judge of the Maricopa County Superior Court and, in 1979, the Arizona Court of Appeals.
Bettman Archive/Getty Images
O'Connor poses with her family after she was nominated to the Supreme Court by President Ronald Reagan in 1981. With her, from left, are her son Jay, son Brian, husband John and son Scott.
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In nominating O'Connor for the bench in 1981, President Ronald Reagan called O'Connor "truly a person for all seasons, possessing those unique qualities of temperament, fairness, intellectual capacity, and devotion to the public good which have characterized the 101 brethren who have preceded her."
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O'Connor is sworn in for her confirmation hearings in 1981.
Scott Applewhite/AP
O'Connor waves outside the US Capitol shortly after her nomination was confirmed by the Senate.
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O'Connor is sworn in by Supreme Court Chief Justice Warren Burger in 1981. Her husband, John, is holding two family Bibles.
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O'Connor stands in front of the Supreme Court after being sworn in as its first-ever female justice.
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O'Connor is seen in her chambers 10 days after she was sworn in.
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O'Connor poses with other Supreme Court justices for an official photo in 1982. With O'Connor in the back row, from left, are John Paul Stevens, Lewis F. Powell Jr. and William Rehnquist. In the front row, from left, are Thurgood Marshall, William J. Brennan Jr., Chief Justice Warren Burger, Byron White and Harry Blackmun.
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O'Connor and her husband, John, visit the Great Wall of China in 1987.
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O'Connor, sitting next to fellow Supreme Court Justice Antonin Scalia, shakes hands with US Sen. Warren Bruce Rudman before a subcommittee meeting in 1992.
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O'Connor dances with her husband, John, at a ball in Washington, DC, in 1998.
Liaison/Getty Images
During her tenure, the court for a time was known informally as the "O'Connor Court" because she served as the deciding vote in so many controversial cases. She was perhaps best noted for her vote in Planned Parenthood v. Casey, a 1992 opinion that reaffirmed a woman's right to an abortion. Under the new ruling a state could not impose an "undue burden" on a woman seeking an abortion. The opinion would be overturned in 2022 by a conservative court bolstered by three of President Donald Trump's nominees.
David Hume Kennerly/Getty Images
O'Connor and fellow Supreme Court Justice Ruth Bader Ginsburg are surrounded by statues of men as they pose together at the US Capitol in 2001.
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From left, O'Connor, Chief Justice William Rehnquist and Justice Anthony Kennedy take part in a groundbreaking ceremony at the Supreme Court in 2003. The court's facilities were being modernized.
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O'Connor is joined by President George W. Bush, left, as she swears in Attorney General Alberto Gonzales in 2005. Gonzales' mother, Maria, is second from left and his wife, Rebecca, is second from right.
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O'Connor receives applause after she spoke at a judicial conference in Spokane, Washington, in 2005. This was a few weeks after she announced that she would be retiring from the court to care for her husband, who was ailing from Alzheimer's disease.
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O'Connor weeps as pallbearers carry the casket of former Chief Justice William Rehnquist in 2005. Rehnquist was her classmate at Stanford Law School, and the two once dated.
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O'Connor waves during the Rose Parade in Pasadena, California, in 2006. She was accompanied by her grandchildren.
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O'Connor speaks at the Justice Department in 2006 as part of an event for Women's History Month.
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O'Connor receives the Lincoln Medal from President George W. Bush in 2008.
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O'Connor speaks at the National Press Club in Washington, DC, in 2008.
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O'Connor talks with Solicitor General Elena Kagan during a forum in Washington, DC, in 2009. Kagan was nominated to the Supreme Court in 2010.
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President Barack Obama presents O'Connor with the Presidential Medal of Freedom in 2009.
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O'Connor and Supreme Court Justice Ruth Bader Ginsburg attend a Women's Conference in Long Beach, California, in 2010.
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O'Connor tours an exhibit about her at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas, in 2011. Growing up on the Lazy B Ranch in Arizona, O'Connor was known for her self-reliance and independence, traits she acquired as a young woman branding cattle, driving tractors and firing rifles.
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O'Connor testifies before the Senate Judiciary Committee in 2012. She spoke to the necessity for civics education in maintaining an independent judiciary. She also expressed doubt about the process in some states of electing judges, and about the validity of asking Supreme Court nominees how they would vote in the future.
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O'Connor receives the Anam Cara Award at the Irish Cultural Center in Phoenix in 2014.

Her husband died in 2009, and she leaves behind three sons.

O’Connor was well aware of the symbolism of her place in history as the first female justice.

“Let me tell you one reason why I think it’s important, and that is for the public generally to see and respect the fact that in positions of power and authority, that women are well-represented,” O’Connor said in a 2003 interview with CNN. “That it is not an all-male governance, as it once was.”

This story has been updated with additional information.