Justice Ruth Bader Ginsburg, 80, vowed to stay on the Supreme Court as long as her health and intellect remained strong, saying she was fully engaged in her work as the leader of the liberal opposition on what she called "one of the most activist courts in history." In wide-ranging remarks Friday, Ginsburg said she had made a mistake in joining a 2009 opinion that laid the groundwork for the court's decision in June effectively striking down the heart of the Voting Rights Act of 1965. The recent decision, she said, was "stunning in terms of activism."

On her health: Ginsburg, who was appointed by President Bill Clinton in 1993, has survived two bouts with cancer but her health is now good, she said, and her work ethic exceptional. "Ever since my colorectal cancer in 1999, I have been followed by the NIH. That was very lucky for me because they detected my pancreatic cancer at a very early stage [in 2009]. After the pancreatic cancer, at first I went to NIH every three months, then every four months, then every six months. The last time I was there they said come back in a year."

Less than three weeks after surgery for that second form of cancer, Ginsburg was back on the bench. She works out twice a week with a trainer.

On retirement: Ginsburg said her retirement calculations would center on her health and not on who would appoint her successor, even if that new justice could tilt the balance of the court and overturn some of her landmark women's rights decisions that are a large part of her legacy. "There will be a president after this one, and I'm hopeful that that president will be a fine president."

On her legacy: "I don't see that my majority opinions are going to be undone. I do hope that some of my dissents will one day be the law."

On her age: "I don't water-ski anymore. I haven't gone horseback riding in four years. I haven't ruled that out entirely. But water-skiing, those days are over." She said she intended to stay on the court "as long as I can do the job full steam and that, at my age, is not predictable. I love my job. I thought last year I did as well as in past terms."

On the court: "I am now the most senior justice when we divide 5-4 with the usual suspects."

"If it's measured in terms of readiness to overturn legislation, this is one of the most activist courts in history." She was especially critical of the voting rights decision, as well as the part of the ruling upholding the health care law that nonetheless said it could not be justified under Congress' power to regulate interstate commerce.

On the last two terms, which brought major decisions on health care law, race and same-sex marriage: They were "heady, exhausting, challenging."

On Congress: "I'd like to think that [Congress will overturn] … the two Title VII [civil rights] cases from this term, but this Congress doesn't seem to be able to move on anything. In so many instances, the court and Congress have been having conversations with each other, particularly recently in the civil rights area. So it isn't good when you have a Congress that can't react."

On the Voting Rights Act: "The Voting Rights Act passed by overwhelming majorities, but this Congress I don't think is equipped to do anything about it." The flaw in the court's decision, she said, was to conclude from the nation's progress in protecting minority voters that the law was no longer needed. She repeated a line from her dissent: "It is like throwing away your umbrella in a rainstorm because you are not getting wet."

On her personal life: She has always been "a night person," she said, but she has worked even later into the small hours since her husband, Martin D. Ginsburg, a tax lawyer, chef and wit, died in 2010. Since then, she said, there is no one to call her to bed and turn out the lights.

On the court's approach: She said that as a general matter the court would be wise to move incrementally and methodically. It had moved too fast, she said, in Roe vs. Wade, the 1973 decision that established a constitutional right to abortion. The court could have struck down only the extremely restrictive Texas law before it. "I think it's inescapable that the court gave the anti-abortion forces a single target to aim at. The unelected judges decided this question for the country and never mind that the issue was in flux in the state legislatures."

On same-sex marriage: In June, the court declined to say whether there was a constitutional right to same-sex marriage, allowing the issue to percolate further. But Ginsburg rejected the analogy to the lesson she had taken from the aftermath of the Roe decision. "I wouldn't make a connection."

On fireworks on the bench: Fireworks at the end of the last term included three dissents announced from the bench by Ginsburg. Such oral dissents are rare and are reserved for major disagreements. One was a sharp attack on Justice Samuel Alito's majority opinion in a job discrimination case, and he made his displeasure known, rolling his eyes and making a face.

"It was kind of a replay of the State of the Union, when he didn't agree with what the president was saying [in 2010 about the Citizens United decision.] It was his natural reaction, but probably if he could do it again he would have squelched it."

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