In many ways, his arc is the country’s arc.
Mr. Biden, 80, was raised in a time when much of the country was less tolerant of people’s sexual orientations. His policy choices in the Senate reflected those times, often siding with those who proposed restrictions, or limits, on gay men and lesbians. He supported a measure that restricted how homosexuality was taught in schools, one of many defeats for the equality movement.
During his 2008 vice-presidential debate with Sarah Palin, Mr. Biden said he opposed “redefining from a civil side what constitutes marriage.” But people close to Mr. Biden said he kept an open mind about the issue and was a keen observer of the ways that society was changing around him — and slowly changed his positions.
“I do respect and appreciate that he is someone that can admit that his views were outdated in the past and that he has evolved on the subject and is now an outspoken champion and advocate,” said Kelley Robinson, the president of Human Rights Campaign, a gay rights organization in Washington. “This is a matter of policy and politicians catching up to where the people already are.”
Mr. Biden also now firmly supports the rights of women to choose to have an abortion, despite having had reservations earlier in his career. A practicing Catholic, the president was once an outright critic of abortion rights but later became a quiet — if uncomfortable — defender of them in the Senate.
Since the Supreme Court’s ruling in June to end the constitutional right to an abortion, Mr. Biden has been fervent in his condemnation of the decision in Dobbs v. Jackson Women’s Health Organization and has repeatedly called for legislation that would replace the 50-year-old court precedent with legal protections for the right of women to have an abortion.
Mr. Biden has also shifted his views on criminal sentencing, an issue that has increasingly brought Democrats and Republicans together in recent years. In 2018, President Donald J. Trump signed the First Step Act, a bipartisan compromise to reform sentencing laws, including mandatory minimum sentences for nonviolent drug offenders.
As a young senator, Mr. Biden repeatedly supported tough-on-crime legislation, culminating in his support for the 1994 crime bill that many in his party now blame for an era of mass incarceration, especially of minorities. In a speech at the time, Mr. Biden bragged that his view of crime was to “lock the S.O.B.s up.”
