Death row inmate Troy Davis denied clemency in Georgia

Troy Davis, the death row inmate due to be executed for the 1989 murder of an off-duty police officer, has lost a final appeal for clemency from the Georgia pardons board.

Davis, 42, is scheduled to be executed by lethal injection Wednesday evening for killing Mark MacPhail in Savannah, Georgia. His lawyers had argued that a lack of physical evidence and dubious witness testimony provided enough doubt about his guilt to spare him the death penalty, The New York Times says.

A last-ditch international campaign to save Davis saw more than 630,000 letters delivered to the Georgia pardons board by Amnesty International, the Times reports. Among the people who asked that the board give him clemency were former U.S. President Jimmy Carter, Archbishop Emeritus Desmond Tutu, singer Cee Lo Green and Pope Benedict XVI.

A spokesman for the Georgia State Board of Pardons and Paroles said the panel made their decision after hearing testimony from both supporters and prosecutors, the BBC reports.

MacPhail's relatives said they were relieved at the decision.

"Justice was finally served for my father," said Mark MacPhail Jr, the victim's son, according to the BBC. "The truth was finally heard."

In 1991 Davis was convicted of murdering MacPhail, who was working as a restaurant security guard when he intervened in an argument in a parking lot and was shot dead.

However since the conviction many of the witnesses have changed their testimony, and there is no clear physical evidence linking Davis to the scene.

Davis has had three brief reprieves from execution after doubts appeared over his conviction.

Since 1976 Georgia has executed 51 people convicted of murder, with clemency granted on only seven occasions.