WASHINGTON — The authors of Alabama's new law criminalizing abortion have left no doubt that they passed it to provoke the Supreme Court into overturning Roe v. Wade's protection of a woman's right to choose. But there's no guarantee that will happen.

Republican state Rep. Terri Collins, one of the law's sponsors, says it was intended to challenge Roe "and hopefully to let that decision go back to the states, so that states can make the laws that are most appropriate for their people."

Planned Parenthood and the American Civil Liberties Union have both said they intend to challenge the law. They will file their lawsuits in federal district court in Alabama, seeking to block enforcement before the law takes effect in six months. Because the lower courts are bound by Supreme Court precedent, judges have no choice but to declare the law unconstitutional.

Alabama would then take the law to the 11th Circuit Court of Appeals in Atlanta, which would also be bound to reach the same conclusion. But the state's right to an automatic appeal ends there. It would have to ask the Supreme Court to take the case, and such a move would face long odds.

The justices most often accept an issue for review when the lower courts are divided — when there's a split among the circuits. But because the spate of recent laws so clearly violate Roe and follow-on Supreme Court rulings, it's most likely that all the appeals courts will declare them unconstitutional, leaving no circuit split.

A second reason Alabama faces a strong headwind is that the law is quite blunt in asking the Supreme Court to overturn 46 years of legal precedent, beginning with Roe in 1973 and reaffirmed repeatedly. But supporters of the state law are hoping that President Donald Trump's newest appointment to the court, Justice Brett Kavanaugh, changed the court's fundamental arithmetic.

He replaced Justice Anthony Kennedy, who voted to reaffirm Roe. Added to Justices Clarence Thomas, Samuel Alito and Neil Gorsuch, that brings to four the number of potential votes to overturn the landmark decision. But it takes five votes to achieve such a ruling, and there's no guarantee Chief Justice John Roberts would provide it, given his interest in the court's long-term legacy.

Even so, the court's liberals suggested this week that they are concerned about that prospect. They dissented Monday when the court struck down a 40-year-old precedent involving lawsuits against the states. Justice Stephen Breyer, writing for himself and for Justices Ruth Bader Ginsburg, Sonia Sotomayor and Elena Kagan, said it is dangerous for the court "to overrule a decision only because five members of a later court come to agree with earlier dissenters on a difficult legal question."

Breyer said "the law can retain the necessary stability only if this court resists that temptation," and one of the factors often cited in deciding whether to overturn precedent is how much the nation has relied upon an earlier ruling.

Harvard Law School professor Laurence Tribe, one of the nation's leading constitutional experts, says overruling Roe and the follow-on case upholding it, Planned Parenthood v. Casey, "would upset much deeper and broader societal reliance interests" than those at issue in this week's case about suing the states.

"So there is cause for concern," Tribe says, "but not panic."

But Ian Millhiser of the Center for American Progress, a liberal advocacy group, says, "With all respect to Professor Tribe, now is the time for supporters of reproductive rights to panic." More likely than overturning Roe, he says, is the prospect that the court would uphold other state laws that seek to limit access to abortion.

Two such laws are now pending before the Supreme Court, waiting for the justices to decide whether to review them. One is a challenge to a Louisiana law that would require any doctor offering abortion services to have admitting privileges at a hospital within 30 miles. It is virtually identical to a Texas law the Supreme Court struck down in 2016.

A second pending case involves an Indiana law, signed by then-governor and now Vice President Mike Pence, that prohibited what the state called discriminatory abortions, those sought because of characteristics of the fetus, including gender, race or diagnosis of Down syndrome or other defect.

If the departure of Kennedy changes the balance and results in the court upholding either of those laws, it would represent a further restriction on abortion without overturning Roe v. Wade, and without a ruling on the law passed by Alabama that is so clearly addressed to the Supreme Court.

"The more extreme the abortion restriction, the less likely it is to get to the Supreme Court soon," said Tom Goldstein, a Washington lawyer who argues frequently before the court. "Pro-life advocates need John Roberts, and he does not rush in to things like this. But there very likely are enough votes to consider a less aggressive statute and narrow Roe."