WASHINGTON — President Biden will sign the Respect for Marriage Act on Tuesday, mandating federal recognition for same-sex marriages and capping his own personal evolution toward embracing gay rights over the course of a four-decade political career.
The landmark legislation, passed by a bipartisan coalition in Congress, officially erases the Defense of Marriage Act, which a quarter of a century ago defined marriage as between a man and a woman, and prohibits states from denying the validity of out-of-state marriages based on sex, race or ethnicity.
The White House has invited several thousands of guests to an elaborate signing ceremony on the South Lawn, complete with musical performances, as the president celebrates passage of what officials are calling a “historic piece of legislation.”
For Mr. Biden, who voted for the Defense of Marriage Act as a senator in 1996 and wavered on letting gay men and lesbians serve in the military, the signing ceremony will be an indication of how much the president has changed when it comes to championing L.G.B.T.Q. equality.
The president was unequivocal in his support for the new legislation, saying earlier this year that he was confident that “Republicans and Democrats can work together to secure the fundamental right of Americans to marry the person they love.”
But it is also a mark of ongoing fear that newfound gay rights may be fragile. The push for passage of the law was driven in part by the Supreme Court opinion overturning abortion rights, in which Justice Clarence Thomas raised the possibility of using the same logic to reconsider decisions protecting marriage equality and contraception rights.
Opponents of the legislation argued that it would undermine family values in the United States and restrict the religious freedoms of people who do not believe that same-sex marriage is moral.
Proponents of the new law argued that Congress needed to be proactive in ensuring that a future Supreme Court ruling would not invalidate same-sex marriages around the country. In 2015, the court ruled in Obergefell v. Hodges that all states must recognize the marriages of same-sex couples just as they would marriages between a man and a woman.
Once a fiercely divisive political issue, same-sex marriage has won mainstream approval in recent years, with polls showing that 70 percent of Americans support it. That broad acceptance was the backdrop for a rare show of bipartisanship in Congress, where 61 senators and 258 House members voted to send the Respect for Marriage Act to Mr. Biden’s desk for his signature.
By the time that happened, there was no doubt that the president would sign it. As a candidate for the presidency in 2020, he was an ardent supporter of gay rights and same-sex marriage. He has appointed scores of L.G.B.T.Q. officials to posts in his administration, including Pete Buttigieg as transportation secretary. Some gay rights leaders have hailed him as the most pro-equality president ever.
As vice president, Mr. Biden publicly announced his support for same-sex marriage before his boss, President Barack Obama, upending careful plans for Mr. Obama’s re-election announcement. In an interview on NBC’s “Meet the Press” in 2012, Mr. Biden said that “I am absolutely comfortable with the fact that men marrying men, women marrying women and heterosexual men and women marrying one another are entitled to the same exact rights, all the civil rights.”
It was a significant moment, especially for one of the nation’s most prominent Catholic politicians. Tuesday’s signing of the marriage bill is the latest evidence that whatever qualms Mr. Biden had during earlier stages of his career have all but evaporated.
“On this day, Jill and I are thinking of the courageous couples and fiercely committed advocates who have fought for decades to secure nationwide marriage equality at the Supreme Court and in Congress,” Mr. Biden said in a statement after House passage last week. “We must never stop fighting for full equality for L.G.B.T.Q.I.+ Americans and all Americans.”