A man wrongfully convicted for a 1989 double-murder in San Francisco has been ordered freed after spending 18 years in prison. Prosecutors told a judge Tuesday that key witnesses are dead or unavailable and they will not retry 40-year-old Caramad Conley for the killings of Roshawn Johnson and Charles Hughes. Conley has been serving two terms of life in prison without parole. The judge last month ruled that Conley was wrongfully convicted because the star witness, police informant Clifford Polk, lied on the stand. Polk has since died.