Chief Justice John G. Roberts, Jr., appears to be leaning – if today’s Supreme Court hearing on abortion rights provides a reliable hint – toward fashioning a ruling that does not take away totally a woman’s constitutional right to end her pregnancy but leaves it much narrowed.

The key to such a decision would be to cast aside the long-standing rule that states may not constitutionally impose a flat ban on abortions until the fetus is capable of living if delivered – that is, has reached “viability.”  That is a point, medically, at about 24 weeks of pregnancy.

Hearings before the Court, in cases as challenging as abortion cases always are, do not produce predictable outcomes but they can create quite firm impressions of where the Justices – individually and together – may be inclined to go.

Here are the most important impressions from today’s nearly two-hour hearing on the constitutionality of a 15-week abortion ban, enacted in 2018 in Mississippi:

** The six conservative Justices, with varying degrees of intensity, think the two major abortion rights precedents – Roe v. Wade (1973) and Planned Parenthood v. Casey (1992) — were either wrong from the beginning or have not stood the test of time.

** But most of the Justices understand that a complete overruling would be a major blow to the Court’s institutional reputation.  (A liberal Justice, Sonia Sotomayor, practically guaranteed such a reaction by saying flatly that such a result would leave “a stench,” with the Court acting out of pure political motive just because its membership had changed.)

** If the precedent is to remain, there is not a majority — five Justices — to keep it intact, as is, even though it has been a binding precedent up to now.  Several Justices seemed unsure of just how far they should feel bound by precedent, but were not so uncertain that they would hesitate to pare back the rulings on abortion rights.

** States, while gaining some wider authority to restrict abortion, would need guidance on how far they may go with new regulations.  The states that want to retain an unrestricted right for a woman to choose an abortion would be assured that they may make that choice.

** The only way to allow more restrictions is to find a way to make the constitutional line at which abortion can be completely outlawed more flexible than it has been for 48 years (since Roe).  That means abandoning “viability” as a fixed line, replacing it with a floating line — probably keyed to stages of fetal development.

** Women would still have to be guaranteed access to abortion when medically necessary, somewhat flexibly defined, but not guaranteed when the choice was merely to end an unwanted pregnancy.   New duties would have to be imposed on doctors’ willingness to perform abortions, but penalties for doctors who broke the law might have to be less harsh.

If those impressions hold when a final ruling emerges sometime next spring or summer, it very likely would mean that Mississippi’s flat ban at 15 weeks of pregnancy, would be upheld but in cautionary language about not feeling free to constantly push a ban ever earlier in pregnancy.

Of course, a ruling along those lines would leave open such questions as:  what about a flat ban at 12 weeks (as some state legislatures have enacted), and what about at six weeks (as in the Texas abortion law that the Justices are separately reviewing)?  Those would have to be left for lower courts to ponder in the first instance, applying whatever new guidance the Supreme Court had provided.

In other words, the abortion issue as a constitutional controversy would not be ended by the ruling in the Mississippi case.  It would remain a dominant part of American’s political and constitutional life.

So far as impressions went, it was quite clear that three of the most conservative Justices – Samuel A. Alito, Jr., Neil M. Gorsuch and Clarence Thomas – would be pressing hard for a decision to flatly overrule both Roe and the Casey sequel.  Even so, they probably would go along with Roberts to help make a six-Justice majority for a compromise decision.  It would be better, for appearances sake, not to splinter the majority in favor of the result.

It also seemed that Justices Amy Coney Barrett and Brett M. Kavanaugh could be persuaded to be a part of a compromise ruling that left Roe substantially changed.

There were no indications that the three most liberal Justices – Sotomayor, Stephen G. Breyer and Elena Kagan – would go along with any ruling that impaired the two precedents in any significant way.  None of the three seemed at all willing to endorse a ruling that, for the first time in history, would take away an individual constitutional right that the Court itself had fashioned.

A ruling along the lines hinted at would be, of course, a profound disappointment to women’s rights advocates.  They have long believed that maintaining the option to end a pregnancy up to the point of fetal “visability” was at the core of the constitutional right.

But from Chief Justice Roberts’ very first question, suggesting that the “viability” line was not really central to either Roe or Casey and even that the late Justice Harry A. Blackmun (the author of the Roe opinion) had disowned that concept, the advocates of a continue abortion right had reason to fear.  The remainder of the hearing gave them no dependable reasons to feel optimistic.

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