The challenges of capital punishment in the military system include the lack of “death-qualified” defense attorneys, and the right to a series of appeals in military and civilian courts. The president also has to personally sign off on the ultimate execution.

Davis was convicted in 1991 of murdering a Savannah, Ga., police officer based on witness testimony that, for the most part, has since been recanted. As I wrote last week, seven out of nine witnesses have said they testified falsely: several couldn’t accurately identify the shooter; two said their testimony was coerced by police, and at least three now blame the murder on another man.

One witness who signed a statement identifying Davis as the killer later said, “I did not read it because I cannot read.” Another said that the police “were telling me that I was an accessory to murder and that I would…go to jail for a long time and I would be lucky if I ever got out, especially because a police officer got killed…I was only 16 and was so scared of going to jail.”

The murder weapon was never recovered, and Davis has consistently maintained his innocence.

Davis’s lawyers have spent the last 10 years trying to get him a hearing based on this new evidence. When their plea reached the Georgia Supreme Court, however, the justices decided by one vote not to grant it.

Even if the witness affidavits the lawyers submitted were true, the majority ruled, recanted witness testimony is never sufficient grounds for a new hearing. Three judges on the court disagreed. The majority’s view “fails to allow an adequate inquiry into the fundamental question, which is whether or not an innocent person might have been convicted or even, as in this case, might be put to death,” they wrote.

The Davis case then reached the U.S. Supreme Court, which had an opportunity to decide whether executing a potentially innocent man violates the Constitution. Last week, the court decided not to decide.

The refusal to grant a hearing on new evidence to a man who may have been wrongly convicted has shocked political and spiritual leaders around the world. Pope Benedict XVI, Archbishop Desmond Tutu, former President Jimmy Carter and the Council of Europe have all weighed in on Davis’s behalf.

Still, Chatham County District Atty. Spencer Lawton, Jr., who remained silent about this case for years, recently wrote in The Atlanta Constitution that he feels just fine about executing Davis on Monday. “The law is understandably skeptical of post-trial ‘newly-discovered evidence,’ ” Lawton wrote. “Such evidence as these affidavits might, for example, be paid for or coerced or the product of fading memory.”

Perhaps, but lawyers for Davis aren’t asking for their client to be freed. They just want a hearing so the witnesses who recanted their earlier testimony can explain why they testified at trial the way they did, and why they’ve changed their minds now. Lawton would presumably be free to ask them at that time whether they’ve been paid, coerced or simply can’t remember exactly what happened 17 years ago.

In a letter to Georgia’s State Board of Paroles and Pardons, the president of the sub-committee on human rights in the European Parliament wrote that this case “epitomizes everyone’s dread regarding the possible execution of an innocent person.” The European Parliament has even passed a resolution calling for Davis to get a new hearing.

Here in the United States, we’ve always assumed that, as the Supreme Court wrote in Herrera v. Collins in 1993, “a truly persuasive demonstration of ‘actual innocence’ made after trial would render the execution of a defendant unconstitutional.”

But the court has never had an opportunity to rule directly on that point before. In petitioning the Supreme Court for review, Davis’s lawyers wrote: “Mr. Davis’s case allows this court an opportunity to determine what it has only before assumed…. that the execution of an innocent man is constitutionally abhorrent.” The high court turned down that opportunity.

Davis could likely be executed amid loud protests on Monday evening, in the tiny town of Jackson, Ga.

Lawyers for the defendant, Troy Anthony Davis, now 40, had hoped the court would grant certiorari to review whether it is constitutional for a state to execute a man where newly discovered evidence indicates he might be innocent.

In denying review without comment, the court cleared the way for Davis’s immediate execution.

Since Davis’s conviction in 1991, two witnesses in the case have said they were pressured by police officers to testify against Davis. Three witnesses have since said another man admitted to the murder. Prosecutors presented no physical evidence or murder weapon supporting Davis’ conviction.

Davis’ lawyers have been arguing for 10 years that the new evidence warrants a new hearing in the case. The Georgia Supreme Court denied that request, concluding that witness recantation alone is insufficient to warrant a new hearing.

Yesterday, Davis’s lead lawyer, Jason Ewart, said he might ask the court to reconsider.