A judge is considering his verdict regarding a 19-year-old Sioux City resident accused of stabbing to death his ex-girlfriend and another man. Testimony ended this week in the nonjury trial of Tran Walker. He's accused of killing 17-year-old Paiten Sullivan and 18-year-old Felipe Negron Jr. Police say Walker was in a car with the other two in January of last year when he stabbed Sullivan and then Negron when he tried to intervene. Walker has pleaded not guilty to the two counts of first-degree