A substantial number of people who once were unwavering supporters of capital punishment have become skeptical. Their conviction that some vicious criminals should pay the ultimate price remains firm.

But revelations that a substantial number of people convicted of crimes were innocent changes everything. No one wants to learn an innocent person has been executed.

In Tennessee, the daughter of a man executed 13 years ago after being convicted of killing a woman is crusading to clear her father’s name. April Alley maintains her father, Sedley Alley, was innocent.

He confessed to killing the woman, but said later that his admission had been coerced. Not long before he was executed, lawyer Barry Scheck, who co-founded the Innocence Project, sought DNA testing in Alley’s case. The request was rejected and Alley was put to death by lethal injection on June 28, 2006.

Scheck’s concern was revived earlier this year, when investigators in Missouri called him about a possible connection between the murdered woman and another man who is charged with sexually assaulting two women and murdering another.

April Alley has been working with the Innocence Project in an attempt to have DNA testing done on evidence in her father’s case.

This week, however, a judge in Memphis said no to the request — on a technicality. She ruled April Alley does not have legal standing to have the DNA testing done. She emphasized her decision had nothing to do with the merits of the case.

Tennessee Supreme Court justices should take up the case. If they cannot see their way clear to order the DNA testing, Tennessee legislators should enact a law that permits it.

Nothing can bring Sedley Alley back to life. But if he was innocent of the crime that sent him to the execution chamber, it is important that everyone learn the truth.