By Lawrence Hurley, Andrew Chung and Makini Brice
WASHINGTON (Reuters) -America's decades-old battle over abortion rights exploded anew on Tuesday as the Supreme Court confirmed a draft opinion that signaled it will soon overturn the landmark 1973 Roe v. Wade ruling that legalized abortion nationwide.
President Joe Biden denounced the expected move as "radical" as Democrats in Washington and in statehouses scrambled to try to find a response to defend a right that women in the United States have held for almost half a century.
Some moderate Republicans were also dismayed but social conservatives were delighted even as they voiced anger that the opinion was leaked.
The court confirmed that the draft opinion, published late on Monday by the news outlet Politico, was authentic but said it did not represent the final decision of the justices, due by the end of June.
Chief Justice John Roberts announced an investigation into how the draft - authored by Justice Samuel Alito of the court's conservative 6-3 majority - was leaked, calling it a "betrayal" of the confidentiality of the judicial process.
"This was a singular and egregious breach of that trust that is an affront to the court and the community of public servants who work here," Roberts said, pledging that the disclosure will not undermine the integrity of the court's operations.
Hundreds of people on both sides of the divide gathered outside the Supreme Court building in Washington. Supporters of abortion rights chanted "off our bodies" and "abortion is healthcare," while their opponents responded: "Pro-choice is a lie, babies never choose to die."
A ruling by the court striking down Roe would give many Republicans and religious conservatives a victory they have chased for decades.
"It's a fundamental shift in American jurisprudence," Biden said of Alito's draft, arguing that such a decision would call into question other rights including same-sex marriage, which the court recognized in 2015.
"If it becomes the law, and if what is written is what remains, it goes far beyond the concern of whether or not there is the right to choose," Biden added, referring to abortion rights.
The Roe decision recognized that the right to personal privacy under the U.S. Constitution protects a woman's ability to terminate her pregnancy.
Biden vowed to work toward getting Congress to pass legislation codifying the Roe ruling and urged voters to back candidates in the Nov. 8 congressional elections who support abortion rights.
Senate Majority Leader Chuck Schumer said the chamber will vote next week on such legislation even though a similar Democratic-backed bill already failed this year.
Amid Republican opposition, the razor-thin Democratic majority is not enough to overcome Senate rules requiring a supermajority to advance most legislation.
Even if the new Senate vote fails, as is almost inevitable, Democrats could use it to bolster their chances in the midterm elections in which Republicans are hoping to regain control of Congress.
Nearly two-thirds of Americans said they are more likely to back candidates who support the right to abortion in the November vote, according to a Reuters/Ipsos poll conducted on Tuesday.
Democrats believe that will help incumbent Democratic senators including Mark Kelly in Arizona and Raphael Warnock in Georgia, and could hurt some incumbent Republicans, such as Senator Ron Johnson of Wisconsin.
'ROCKS MY CONFIDENCE'
U.S. Senators Lisa Murkowski and Susan Collins, moderate Republicans supportive of abortion rights, voiced dismay at Alito's draft.
"If it goes in the direction that this leaked copy has indicated, I would just tell you that it rocks my confidence in the court right now," Murkowski said, adding she supports legislation codifying abortion rights.
Republican Senator Lindsey Graham welcomed the news.
"If the Supreme Court overturns Roe v. Wade, which I believe was one of the largest power grabs in the history of the Court, it means that every state will decide if abortion is legal and on what terms," Graham said. "That, in my view, is the most constitutionally sound way of dealing with this issue and the way the United States handled the issue until 1973."
The person who leaked the draft has not been identified.
Senate Republican Leader Mitch McConnell condemned the leak as a "lawless action" and said it was part of a campaign by the "radical left," but offered no evidence.
STATE LAWS
If Roe is overturned and no federal legislation is passed, abortion law would be determined by the states. Abortion likely would remain legal in liberal-leaning states while conservative states would be free to ban it.
States have already passed a raft of abortion-related laws. Republican-led states have moved swiftly, with new restrictions passed this year in at least six states. On Tuesday, the governor of Oklahoma signed a ban outlawing abortions after six weeks, before many women know they are pregnant.
At least three Democratic-led states this year have passed measures to protect abortion rights.
Abortion provider Planned Parenthood said it was horrified by the draft ruling, although its clinics remain open for now.
"While we have seen the writing on the wall for decades, it is no less devastating," said Alexis McGill Johnson, the group's president.
The case at issue involves a Republican-backed Mississippi ban on abortion starting at 15 weeks of pregnancy, a law blocked by lower courts.
"Roe was egregiously wrong from the start," Alito wrote in the draft opinion https://www.politico.com/f/?id=00000180-874f-dd36-a38c-c74f98520000.
Roe allowed abortions to be performed before a fetus would be viable outside the womb, between 24 and 28 weeks of pregnancy. Based on Alito's opinion, the court would find that Roe was wrongly decided because the Constitution makes no specific mention of abortion rights.
"Abortion presents a profound moral question. The Constitution does not prohibit the citizens of each state from regulating or prohibiting abortion," Alito wrote.