Along with it, another case on abortion will also be affected: Planned Parenthood of Southeastern Pennsylvania v. Casey. The 5-4 decision upheld Roe in 1992, but paved the way for more restrictions on abortion access because it declared that restrictions were allowed as long as there was not an "undue burden." It was the first time the court set a new standard on validity of certain laws that restricted abortions.
"Roe and Casey are the twin pillars of the court's jurisprudence," on abortion, Melissa Murray, a professor of law at New York University, told NPR.
What was Planned Parenthood v. Casey about?
In 1988 and 1989, Pennsylvania changed its abortion laws and added several restrictions for certain people seeking abortions.
The changes required informed consent and a 24-hour waiting period before someone could receive an abortion. In most instances, a minor seeking an abortion had to get consent from at least one parent. And if a married woman sought an abortion, she had to say that she had notified her husband.
Several doctors and abortion providers sued and the case went to a district court, which ruled that the law was unconstitutional. An appeals court — which then included Alito — said all of the state's restrictions were allowed, except for the requirement for a married woman seeking an abortion to say she had gotten consent from her spouse. Alito was the lone dissenting judge in that ruling.
The Supreme Court upheld the appellate court's decision.
What did the court decide?
The court ruled in favor of Planned Parenthood, saying that the right to an abortion was still protected.
But Casey also changed some aspects of what had been determined in Roe.
Under Roe, a trimester framework was used to set standards on when an abortion could be restricted. In the first trimester of pregnancy, an abortion was unrestricted. In the second trimester, the state was allowed to add some restrictions but not outlaw abortions in the interest of the pregnant person's health. In the third trimester, the fetus is considered viable, and the state could regulate or outlaw abortions in the interest of the fetus, except when it was necessary to preserve the life or health of the pregnant person.
Casey essentially scrapped the trimester framework. The justices said that in order to keep the right to an abortion but also recognize that the state has a "profound interest in potential life," there should be a new standard of "undue burden" applied.
As long as an abortion restriction does not add an extra burden or "substantial obstacle" onto the person seeking an abortion before the fetus is viable, the restriction is allowed. And that's how the legality of abortion restrictions have been determined since 1992.
So how does 'undue burden' get decided?
This is where it gets complicated: What constitutes a burden?
That grey area opened the door for states to pass laws that required counseling before an abortion, waiting periods and parental involvement for a minor. There were also additional physician and hospital restrictions added in some states.
And it was up to judges to determine whether these state laws could be considered burdens. That led to "incredibly subjective" decisionmaking, Khiara Bridges, a professor of law at the University of California, Berkeley, said.
"When we're asking 'Does it impose an undue burden?' which person are we talking about? If it's an affluent person with a car and credit cards, very few abortion regulations would impose an undue burden," Bridges said.
"But for a poor person who lives in rural areas and doesn't have a car, a two trip requirement to an abortion clinic because there's a 24 hour period, that would be an incredible burden on that person," she said
Why was Casey so important legally?
Most importantly, Casey upheld Roe, saying that the right to an abortion was protected. In other words, it followed what it is called stare decisis, or following the precedent set by previous cases the court has decided on.
It is not common for the court to backtrack on its own opinions; there is a long history of respecting the precedent that has already been set. Even in the court's opinion on Casey, justices write about how the court can't just bend to political or social pressures to change what has been previously determined. They said there would be a cost of "both profound and unnecessary damage to the Court's legitimacy."
"It is therefore imperative to adhere to the essence of Roe's original decision, and we do so today," justices wrote in 1992.
That's partly why Justice Alito's draft opinion is considered so shocking. It reverts back on not one, but two decisions the Court has made in the past to say the right to an abortion is protected.
If the draft opinion becomes the court's decision, what happens to Casey?
There are parts of Casey, like saying the state has has a profound interest in potential life, that could remain, but the aspects of Casey that upheld Roe in saying that a right to an abortion is protected would likely be revoked.
"We therefore hold that the Constitution does not confer a right to abortion. Roe and Casey must be overruled," Alito wrote in the leaked draft opinion. "The authority to regulate abortion must be returned to the people and their elected representatives."
Bridges said that the draft opinion is just making it clear that none of the precedents of abortion law should remain.
"I think it would have been sufficient to say Roe is not good law, and as a result, Casey is not good law, but I think the draft opinion is just being clear that there is no part of abortion jurisprudence that remains good law," Bridges said.