What would it really take for abortion to be illegal in Pa., N.J.?

Following Justice Anthony M. Kennedy's announcement Wednesday that he's retiring from the U.S. Supreme Court, it's become clear that the decision in Roe v. Wade is at risk.

But what would it really take for it to be overturned?

A handful of analysts have suggested that abortion could be illegal in 20 states within the next 18 months. Social media rang with calls urging girlfriends to obtain intrauterine devices, which can prevent pregnancy for up to a decade, as a precautionary mechanism should abortion be criminalized. And while abortion opponents feel optimistic — Michael Geer, president of the Pennsylvania Family Institute, said the new vacancy on the court provides "a brighter horizon" — advocates for abortion access are gravely concerned.

"I have never been like 'the sky is falling,'" said Carol Tracy, executive director of the Philadelphia-based Women's Law Project. "I am now."

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In truth, a lot would have to happen for abortion access to disappear in Pennsylvania. And if abortion were criminalized in the Keystone State, experts say, the same almost certainly wouldn't happen in New Jersey.

Here's what would need to take place for abortion to be  banned in our area.

David Cohen, a law professor at Drexel University's Thomas R. Kline School of Law, said Kennedy really sided with abortion rights advocates only twice, but both times — in 1992 and in 2016 — his presence on the court made a "huge" difference in landmark decisions that upheld a woman's right to access abortion without "undue burden."

That dynamic will likely change should President Trump follow through on his promise to nominate a justice who would be in favor of overturning Roe. If that person were to be confirmed, he or she would likely become the fifth justice on the court in favor of overturning the decision.

Next, a number of scenarios would have to trigger the court to decide on a case.

Four justices have to sign on in order to accept a case to be argued before the Supreme Court, while five justices are needed for a majority opinion. The court could wait for a state to pass a bill criminalizing abortion, allow that to snake through the lower court system and then make its way to the Supreme Court to be considered. Or, Cohen explained, it could take up one of dozens of pending cases related to abortion-restriction laws. By upholding a law that, say, banned abortion after 20 weeks or outlawed certain types of procedures, the court could effectively overturn Roe v. Wade.

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Cohen said that if Roe were to be overturned, 20 states or more — though not Pennsylvania or New Jersey — would be in a political position to immediately pass laws criminalizing abortion. And, he added, an 18-month timeline isn't out of the question should the nomination process go smoothly and the court takes up an abortion case in the next session.

Other scholars say it would likely take longer.

Lisa Tucker, an expert on the Supreme Court and also a professor in Drexel's Kline School, said cases can often take three to four years just to make it to the highest court. She said it's possible the court could chip away at Roe incrementally instead of overturning it outright. There have already been some smaller decisions like this, including laws upheld that allow for waiting periods before an abortion is performed. Tucker said Chief Justice John G. Roberts Jr. "prefers to do things incrementally."

Perry Dane, a law professor at Rutgers Law School who clerked in the 1980s under former Justice William J. Brennan Jr., said the last time there was concern that Roe could be overturned was during Planned Parenthood v. Casey, the 1992 case challenging Pennsylvania abortion restriction laws. He said the rationale of the majority wasn't that they agreed necessarily with the Roe decision — they were more or less inclined to abide by precedent that had been in place since 1973.

It's not clear the current court would have the same concern about overturning long-term precedent — a case decided this week overturned a 40-year precedent affecting unions.

If Roe were to be overturned through a Supreme Court ruling, that decision wouldn't itself criminalize abortion. Instead, the decision would leave it up to states to regulate. What's unclear is what would happen in the immediate aftermath of such a ruling. Dane said it's possible state laws would revert to what they were in 1973 when Roe was decided. At that time, abortion was illegal in Pennsylvania and New Jersey. But he said he's skeptical state courts would interpret the rules that way.

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"Given how much time has passed, given the fact that state legislatures haven't had incentive to repeal those laws because they were struck down," he said, "I can imagine state courts saying those laws don't simply come back to life."

In that case, new laws would need to be passed to change the status quo. Experts, plus advocates from both Planned Parenthood and the abortion-opposing Pennsylvania Family Institute, agree there's long been an appetite in the Pennsylvania legislature to pass a bill further restricting access to the procedure.

Dayle Steinberg, CEO of Planned Parenthood of Southeastern Pennsylvania, said "we can pretty much guarantee" that the Republican-controlled legislature would introduce and have the votes to pass a bill significantly limiting abortion, though it's unclear what that might look like.

Pennsylvania state law allows for women to seek abortions before fetal viability, generally considered about 24 weeks. The legislature last year passed a 20-week abortion ban, which Gov. Wolf vetoed. There's also been some support for a "heartbeat bill," which would ban an abortion once a doctor can detect a fetal heartbeat, usually around six weeks into pregnancy.

A bill of that nature is highly unlikely in New Jersey, where Democrats control the state legislature and the office of the governor. Casey Olesko, a spokesperson for Planned Parenthood Action Fund of New Jersey, said New Jersey has relatively strong abortion-access protections and it doesn't have any laws on the books that restrict abortion in the absence of Roe.

Tracy, of the Women's Law Project, said abortion access in Pennsylvania could come down to having a governor who would veto legislation restricting, banning, or criminalizing abortion.

Wolf, a Democrat, has vowed to deny any such legislation. He vetoed the 20-week abortion ban in December, said he would veto a so-called heartbeat bill, and Planned Parenthood has pledged $1.5 million to support his bid this year for a second term. Beth Melena, a spokesperson for Wolf's campaign, said in a statement that Wolf "is the last line of defense against attacks on women's health in Pennsylvania."

Wolf is running against Republican Scott Wagner, a now-former state senator from York County who is antiabortion, in the November election. Wagner's spokesperson Andrew Romeo wouldn't answer questions about specific abortion-related bills in the absence of Roe, saying only that Wagner will "review any bill that comes before him and make a decision based on the specifics of the legislation."

As a senator, Wagner cosponsored and voted in favor of the 20-week abortion ban and has signaled his support for a heartbeat bill.