A Texas pardons and parole board will today decide the fate of Gary Graham hours before he is due to be executed by lethal injection.
Graham's case has aroused serious concern that he may be innocent of the murder in 1981 for which he was sentenced to death when he was 17. He was convicted solely on the evidence of one eyewitness and now three of the jurors have said that new evidence has led them to doubt his guilt.
Protesters against the execution have been demonstrating outside Governor George Bush's official residence in Austin. He has also been heckled by opponents of the death penalty while campaigning for the presidency in California. Texas is the leading state for executions and 134 have taken place since Mr Bush became governor in 1995.
The Rev Jesse Jackson has visited Graham and has offered to be present at his execution if all attempts at a reprieve fail.
Unease at the implementation of the death penalty in the US has now become an issue in the presidential election as investigations reveal that substantial numbers of death sentences have been set aside because of irregularities.
In the case of Graham, who is African-American, his lawyer has been criticised for failing to challenge the eyewitness evidence and to seek other witnesses. But the eyewitness, an African-American woman, continues to insist that she was not mistaken in identifying Graham as the man who shot dead Mr Bobby Lambert in a car-park.
Graham has admitted going on a crime rampage at that time which involved the rape of a middle-aged woman but he has strongly denied that he was responsible for the murder.
Governor Bush has the power to commute the death sentence or pardon Graham but only on the recommendation of the Texas Board of Pardons and Paroles. The 18 members will fax or telephone their individual views just three hours before Graham is due to be executed.
State Senator Rodney Ellis has asked the board chairman, Mr Gerald Garrett, that the members exceptionally hold a public hearing on Graham's plea for a pardon. Mr Ellis, as the president pro-tem of the Senate, is the acting chief executive in Texas while the governor and his deputy are out of the state.
Mr Garrett decided to postpone the board's decision until today to consider new information that has emerged but said the likelihood of a public meeting was "remote".