Lawyers for an Alabama death row inmate are asking the US Supreme Court to maintain a court-ordered halt to his execution. Attorneys for Vernon Madison told the court today his execution should remain blocked until an appeals court can review claims that strokes and dementia have left him mentally incompetent for lethal injection. The 11th US Circuit Court of Appeals stopped the execution just seven hours before Madison was set to die tonight for the shooting death of Mobile police officer Julius Schulte in 1985. The Alabama attorney general's office is asking the high court to let the execution proceed as planned before the death warrant expires at midnight. The state argues that a county court last month found Madison competent for execution.