The execution of Troy Davis, a Georgia death row inmate scheduled to die in less than a week, should be halted because of "pervasive, persistent doubts" about his guilt, said William S. Sessions, a former federal district judge in Texas and FBI director under Presidents Ronald Reagan, George H.W. Bush and Bill Clinton, in a sharply-worded editorial on Thursday.

"Serious questions about Mr. Davis' guilt, highlighted by witness recantations, allegations of police coercion, and a lack of relevant physical evidence, continue to plague his conviction," Sessions wrote. He urged a state pardons board to commute the sentence to life in prison.