Convicted cop-killer Mumia Abu-Jamal lost his final appeal for a new trial Monday when the U.S. Supreme Court refused to take up the issue of whether blacks were unfairly excluded from the jury. But stay tuned. It seems the justices have not yet had their last word in Abu-Jamal’s case. And there’s a strong hint in the air that, when they do, which may not be until next term, they could be gearing up to reinstate Abu-Jamal’s death sentence.

The outcome in Abu-Jamal’s case just might hinge on what the justices decide to do in the case of a cross-dressing, neo-Nazi triple murderer from Ohio whose case is headed to the high court for a second full-fledged appeal.

More on that in a moment.

In a move that left some court watchers scratching their heads, the justices on Monday turned down Abu-Jamal’s petition, but made no decision about whether to take up a companion petition for certiorari filed by prosecutors demanding reinstatement of Abu-Jamal’s death sentence.

Court records show that prosecutors from the Philadelphia District Attorney’s Office recently filed a supplemental brief in their cert petition in Abu-Jamal’s case — a move that could have caused the justices to delay issuing any ruling.

Court watchers focus on the date that a case is sent to conference. For Abu-Jamal’s petition, that date was April 3 and the order denying his petition was handed down like clockwork the following Monday.

But the district attorney’s petition was scheduled for conference March 20, yet no order has come down on whether the case will be heard. However, an even more compelling hint about what just might be on the minds of the justices came a few weeks back, on Feb. 23, when the high court announced that it had granted certiorari in Smith v. Spisak — an Ohio case that raises strikingly similar issues to those in the prosecutors’ appeal in Abu-Jamal’s case.

Why is Abu-Jamal’s case so similar to that of Frank G. Spisak? Both were on death row for notorious murders, but both won rulings in federal court that granted them partial new trials limited to the penalty phase.

In both cases, the federal courts’ decisions to overturn the death sentences hinged on Mills v. Maryland — a 1988 U.S. Supreme Court decision that governs how juries should deliberate during the penalty phase of a capital trial.

The Mills ruling struck down a Maryland statute that said juries in capital cases must be unanimous on any aggravating or mitigating factor.

The justices declared that unanimity was properly required for any aggravating factor, but that mitigating factors — those that weigh against imposing a death sentence — must be handled more liberally, with each juror free to find on his or her own.

The question now before the courts is whether Mills requires that death sentences in other states be overturned if the juries in those states are misled by faulty instructions or verdict forms to believe that mitigating factors require unanimity.

Perhaps even more important to the justices is a corollary question of federalism: Is it fair for the federal courts to overturn a state court’s decision on how to interpret Mills by imposing its own interpretation that extends Mills beyond its original scope?

The justices may decide to answer that question in Abu-Jamal’s case.

But even more likely is that the justices will provide an answer in Spisak’s case that will be immediately applied to Abu-Jamal’s case — with Abu-Jamal and his lawyers forced to simply watch and wait until that happens.

Spisak, 57, was sentenced to death in 1983 for killing three people at Cleveland State University after a monthlong trial that reportedly included testimony that he was a neo-Nazi and cross-dresser.

In 2006, the 6th U.S. Circuit Court of Appeals overturned Spisak’s death sentence based on a Mills violation as well as findings that his lawyers were ineffective and had “demonized” Spisak during the trial.

The Supreme Court overturned the ruling and ordered the 6th Circuit to study the case again in light of two other decisions by the high court.

But the 6th Circuit in 2008 reinstated its prior decisions, finding they were correct.

Now the Supreme Court has taken the Spisak case up a second time to tackle the question of whether the 6th Circuit failed to give proper deference to the Ohio state courts “when it applied Mills v. Maryland to resolve … questions that were not decided or addressed in Mills.”

In an interview, Abu-Jamal’s lead lawyer, Robert R. Bryan of San Francisco, said “the issue in Spisak is very similar to the issue in our case.”

“The question we’ve got,” Bryan said, “is whether we’ll be left dangling in the wind until Spisak is decided.”