RICHMOND, VA. ? A new round of DNA tests that death penalty opponents believed might finally prove that an innocent man was executed in the United States confirmed instead that Roger Keith Coleman was guilty when he went to the electric chair in 1992.

In a case closely watched by both sides in the death penalty debate, Gov. Mark Warner announced that testing on DNA taken from sperm proved Coleman committed the 1981 rape and murder of his sister-in-law, Wanda McCoy.

Coleman went to his death proclaiming his innocence, and a finding that he was unjustly executed would have been explosive news that almost certainly would have had a powerful effect on the public’s attitude toward capital punishment. Death penalty opponents have argued for years that the risk of a grave and irreversible mistake by the criminal justice system is too great to allow capital punishment.

“We have sought the truth using DNA technology not available at the time the commonwealth carried out the ultimate criminal sanction,” Warner said in a statement. “The confirmation that Roger Coleman’s DNA was present reaffirms the verdict and the sanction. Again, my prayers are with the family of Wanda McCoy at this time.”

Coleman was convicted and sentenced to death in 1982 for the murder of McCoy, his wife’s sister, who was found raped, stabbed and nearly beheaded in her home in the coal mining town of Grundy.

Initial DNA and blood tests in 1990 placed Coleman within the 0.2 percent of the population who could have produced the semen at the crime scene. But his attorneys said the expert they hired to conduct those initial DNA tests misinterpreted the results.

The governor agreed last month to a new round of more sophisticated DNA tests in one of his last official acts. Warner, who has been mentioned as a possible Democratic candidate for president in 2008, leaves office on Saturday.

The report from the Centre of Forensic Sciences in Toronto concluded there was almost no conceivable doubt that Coleman was the source of the sperm found in the victim.