If the Supreme Court overturns Roe v. Wade, the 1973 ruling that established a constitutional right to abortion in America, it would reshape women’s reproductive rights across the country.
A leaked draft of a Supreme Court ruling in Dobbs v. Jackson Women’s Health Organization, first reported by Politico Monday evening, would overturn Roe and return decisions about the legality of abortion to the states. Many states are considering or have passed so-called trigger laws, and other measures, that would rapidly curtail or outlaw abortion in the wake of such a ruling.
The Court is expected to issue its final ruling in Dobbs by the end of June, but the publication of the draft, and Politico’s reporting that a majority of Supreme Court justices support overturning Roe, has focused attention on where abortion rights are most likely to be rolled back.
“We hold that Roe and Casey must be overruled,” Justice Samuel Alito writes in the draft document. In addition to Roe, the 1992 case of Planned Parenthood v. Casey has upheld the constitutional right to abortion, and together they prohibited states from banning abortion before about 24 weeks, when a fetus is viable outside the womb.
The Supreme Court confirmed on Tuesday that the leaked draft opinion is authentic, but noted that the Court’s decision in the case, which was argued Dec. 1, is not final and could still change before the justices ultimately issue their ruling.
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Politicians and activists on both sides of the abortion debate reacted quickly to the leak, launching intense preparations for a likely new era of abortion in the U.S. There is no federal law protecting abortion, so rolling back Roe would create a starker patchwork of legality and access across the country. Some conservative-led states would quickly ban abortion, while others would push to restrict abortion in various ways and other, liberal-led states would protect abortion rights.
If the Supreme Court does overturn Roe, abortion would be outlawed in about half of the states. Most of this would happen through “trigger laws,” which are designed to take effect shortly after the Court strikes down Roe. Other states have laws on the books that were passed before 1973 that they could try to bring back, while still others have passed abortion restrictions in recent years that were blocked by courts, but which they could try to implement once Roe is no longer the law of the land.
Because of the varied state laws at play, there are several different forecasts of how many states will ban abortion. The Guttmacher Institute, a research firm that tracks abortion policy and supports reproductive rights, has estimated that 27 states are likely to ban abortion once Roe is gone. These include: Alabama, Arizona, Arkansas, Florida, Georgia, Idaho, Indiana, Iowa, Kentucky, Louisiana, Michigan, Mississippi, Missouri, Montana, Nebraska, North Carolina, North Dakota, Ohio, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Utah, West Virginia, Wisconsin and Wyoming.
The Center for Reproductive Rights, a legal group that fights abortion restrictions and tracks state laws, counts 25 states as likely to ban abortion. It includes Pennsylvania but not Florida, Iowa or Montana.
Once the Court issues its final ruling, changes could start happening quickly. Of the 13 states with trigger laws, those in Kentucky, Louisiana and South Dakota appear set to take effect immediately. In Arkansas, Mississippi, Missouri, North Dakota, Oklahoma, Utah and Wyoming, state attorneys general or other officials must take action to put the bans in effect. In Idaho, Tennessee and Texas, the laws would take effect 30 days after the Court strikes down Roe.
Read More: What to Know About the Leaked Supreme Court Draft Opinion
The leaked opinion draft could speed this process, says Elizabeth Nash, who tracks state abortion policy for Guttmacher. Though the leaked opinion is not final, it allows states to line up their legal arguments in favor of implementing other abortion restrictions. “Everyone was expecting that Roe would be substantially damaged, perhaps overturned. Now we see where the court is going, which means that there’s now a roadmap for how attorneys general are going to respond in these conservative states,” Nash says.
Six states have bans on abortion that were passed before 1973 and have not been repealed. And a number of others have passed laws in the last few years that courts have blocked because they were in violation of Roe v. Wade. If that precedent goes away, the states can try to bring those laws back into effect.
Meanwhile, states like California, Colorado and Connecticut have passed laws protecting abortion in their state laws, and the glimpse at the Supreme Court’s draft decision could encourage more liberal states to add extra protections.
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Write to Abigail Abrams at abigail.abrams@time.com