His appellate counsel later made a motion for a new trial and asked to have the gloves tested for DNA evidence. The court allowed this, and the results showed that there was female DNA on the outside of the gloves and male DNA — but not Mr. Bharadia’s — on the inside.

The court declined to order DNA testing of Mr. Flint, and no new trial went ahead. But several years later, the Georgia Innocence Project took on Mr. Bharadia’s case, and his new attorneys filed a motion that the DNA results be run through the national Codis DNA database. Finally, in 2012, there was a hit: The male DNA belonged to Mr. Flint.

With this new evidence, Mr. Bharadia’s lawyers moved once again for a new trial, so that a jury could consider the DNA evidence suggesting that Mr. Flint, rather than Mr. Bharadia, had worn the gloves used during the assault. However, under Georgia precedent, a defendant is not entitled to a new trial based on new evidence if the court finds that he could have discovered the evidence at the time of the original trial, had he or his lawyer been diligent enough. Such requirements, which are common, are designed to prevent convictions from being endlessly re-examined.

The Georgia Supreme Court ultimately ruled that nothing prevented Mr. Bharadia’s original attorney from requesting DNA testing of the gloves before the trial. (I filed an amicus brief in this case.) Mr. Bharadia’s motion for a retrial was therefore denied — even though the trial court recognized that this evidence “would probably produce a different verdict.”

Of course, the DNA match does not establish Mr. Bharadia’s innocence beyond all doubt. But he continues to serve a life sentence for a crime that the court acknowledges he probably didn’t commit.

What is most troubling about the Georgia Supreme Court’s decision is that the issue of innocence becomes irrelevant if there has been a failure of due diligence. In effect, the ruling elevates finality over justice to the point that an innocent person can be imprisoned, even executed, because of errors made by his lawyer. Absent a constitutional safety net, an innocent person convicted after a procedurally adequate trial is out of luck.

Faulty convictions happen for many reasons: because juries are composed of human beings, who are fallible; because witnesses feel certain but can be mistaken; and because defense lawyers, particularly those representing indigent defendants, are notoriously overworked and underpaid. The issue is what courts should do in the face of strong evidence that the wrong person has been punished.

Mr. Bharadia now has a habeas corpus petition pending that seeks his release from unlawful imprisonment. If denied by Georgia courts, his case would present an excellent vehicle for the United States Supreme Court to decide, once and for all, that incarceration or execution of an innocent person is constitutionally impermissible.