In Cook County, it is possible for someone to be held in jail on a drug charge for more than three weeks even if they had no drugs.Those charged with drug possession have to wait 24 days on average just to get to a preliminary hearing at which a judge determines probable cause. Other cases involving more serious crimes (including crimes of violence) get to their preliminary hearings within eight to 12 days.In 2013, judges in Cook County determined that 27 percent of drug possession cases — 6,116 — were not …