The emergency actions announced late Thursday showed Chief Justice John Roberts siding with the court's liberals - for now - in blocking a restrictive Louisiana abortion law and keeping the status quo in place.
The ruling provided the best evidence so far about the leanings of justices chosen by President Donald Trump on the issue of abortion; both Justices Neil Gorsuch and Brett Kavanaugh would have allowed the law to go into effect.
And, in the death penalty case, Justice Elena Kagan wrote a powerful dissent that said her conservative colleagues were so intent on hastening executions that they were willing to overlook a "core principle" of religious neutrality.
Both actions came on emergency requests: in one, to stop the Louisiana law from being enforced and, in the other, to allow the execution of a Muslim inmate in Alabama that a lower court had blocked.
In cases on what has been called the court's "shadow docket," those in the majority typically do not provide detailed reasoning for why they granted or denied the requests.
Thus, while Roberts' role in joining the court's four liberals to block the Louisiana law is significant, and determined the outcome, his motives are only a matter of speculation.
It would have been far more telling if he had allowed the law to go into effect.
Even Louisiana acknowledged that its law - which requires doctors at abortion clinics to have admitting privileges at nearby hospitals - is nearly identical to a Texas law that the Supreme Court in 2016 found to be unconstitutional.
In that decision, Whole Woman's Health v. Hellerstedt, a five-member majority said the law "provides few, if any, health benefits for women, poses a substantial obstacle to women seeking abortions, and constitutes an 'undue burden' on their constitutional right to do so."
Roberts was a dissenter in that case, and his actions Thursday was seen in some conservative corners as a betrayal. But it seems inevitable that the court will grant the Louisiana case for full review in its next term, and Roberts' decision on the stay request is not a forecast of whether he will stick with the court's precedent at that time.
Has Roberts "committed himself to reaffirming Whole Woman's Health or any of the court's other abortion decisions? No, of course not," Cornell law professor Michael Dorf, who closely follows the court, wrote on his blog.
But Dorf still found the decision significant. "It does suggest that he is at least in a go-slow mode."
Roberts may yet determine, as the divided U.S. Court of Appeals for the 5th Circuit did in upholding the Louisiana law, that the Supreme Court's earlier decision requires a fact-intensive examination of conditions in the state. The appeals court discounted findings by a district court and assertions by the challengers that the law would force most abortion clinics to close and leave only one or two doctors eligible to perform the procedure.
The chief justice so far in his tenure has never found an abortion restriction unduly burdens a woman's right to the procedure.
In their first major test on the issue, Gorsuch and Kavanaugh met the expectations of the antiabortion groups that supported their nominations. Gorsuch joined Justices Clarence Thomas and Samuel Alito in saying the law should go into effect; none of the three provided their reasoning.
Kavanaugh did, in a dissent that no other justice joined. He said Louisiana had offered the equivalent of a 45-day grace period, in which doctors could have redoubled their efforts to obtain admitting privileges. If that proved insurmountable, the challengers could come back to the court, he said.
If "one or two of the three clinics would not be able to continue providing abortions . . . then even the state acknowledges that the new law might be deemed to impose an undue burden for purposes of Whole Woman's Health," Kavanaugh wrote.
Kavanaugh's opinion might at some point be seen as a compromise. But abortion rights groups who opposed his nomination took it as confirmation that he is hostile to the right to abortion established in Roe v. Wade.
"Even as a bare majority of the Supreme Court made the correct decision, Justice Kavanaugh found a way to prove conclusively what everyone already knows: that he intends to use his position on the court to attack reproductive freedom," People for the American Way executive vice president Marge Baker said in a statement.
In the death penalty case, it was the conservatives who prevailed, and the liberals who complained.
Domineque Ray, who brutally raped and murdered a 15-year-old in 1995, had asked prison officials to allow an imam to be in the death chamber for his execution. But the department said only corrections employees, which included a Christian chaplain, could be nearby during an execution.
A panel of the U.S. Court of Appeals for the 11th Circuit earlier this week stopped the execution and ordered expedited briefing in the case.
"We are exceedingly loath to substitute our judgment on prison procedures for the determination of those officials charged with the formidable task of running a prison, let alone administering the death penalty in a controlled and secured manner," the panel said. "Nevertheless, in the face of this limited record, it looks substantially likely to us that Alabama has run afoul of the Establishment Clause of the First Amendment."
But the Supreme Court's conservatives, this time including Roberts, overruled. Without mentioning the claim's religion aspects, they said in an unsigned order that Ray should have made his request and filed his suit earlier.
Kagan dissented, along with fellow liberal Justices Ruth Bader Ginsburg, Stephen Breyer and Sonia Sotomayor, and called the court's decision "profoundly wrong."
She disputed that the filing came too late, and said the majority was ignoring a potentially meaningful constitutional issue.
Under Alabama's policy, "a Christian prisoner may have a minister of his own faith accompany him into the execution chamber to say his last rites," Kagan wrote.
"But if an inmate practices a different religion - whether Islam, Judaism, or any other - he may not die with a minister of his own faith by his side. That treatment goes against the Establishment Clause's core principle of denominational neutrality."
Ray was allowed to meet with an imam earlier, and the religious leader watched from an adjoining room as Ray was put to death an hour after the Supreme Court rejected the stay request.