Napoleon Beazley was 17 years old when he shot and killed 63 year old John Luttig. He is now 25 and is scheduled to be executed Wednesday.
From its headquarters in Strasbourg, France, the Council of Europe made public a statement it sent to Texas Governor Rick Perry asking for clemency for Beazley. "It is a matter of human decency," the council said, "to right the wrong before it is too late."
Council President Lord Russell-Johnston and Secretary General Walter Schwimmer said Beazley's execution would run against international legal standards and the norms of civilized society.
Amnesty International and the European Union have also called for clemency for Beazley.
The case has drawn international attention because of Beazley's young age at the time he killed Mr. Luttig, and also because the victim's son is a judge in the U.S. court of appeals.
Beazley confessed to the killing, but sought a review of his case over the issue of whether the U.S. constitution bars executing people who were under age 18 when they committed crimes.
However, the issue deadlocked the 9 member U.S. Supreme Court. Three justices excused themselves because Mr. Luttig's son had either worked for or advised them. Of the remaining justices, half were in favor of a reprieve and half against.
The Council of Europe has been an outspoken critic of the death penalty. In June, it threatened the United States and Japan with the loss of their observer status in the group unless they stopped practicing capital punishment by 2003.