A probable cause hearing has been scheduled for Friday for a Detroit woman involved in a fatal stabbing on a Detroit bus. 29-year-old Tiffanie Edwards has been charged with first degree murder in the stabbing death of 50-year-old Charla Williams. Police say Williams, who has a walker, was trying to get off of the bus when she may have accidentally bumped Edwards, who was also trying to get off of the bus. It is charged that Edwards got upset, an argument ensued and Williams was stabbed several times. Edward’s attorney says it was Williams who attacked his client.