When police saw what was left of Carol Ryan’s body, dumped in the driveway of a suburban compost site, they wondered what weapon could cause that level of devastation. The truth was grislier than anyone imagined, and the unsolved mystery of Carol’s murder has haunted Central New York for 27 years.    Carol’s only son blames police. After hundreds of interviews, investigators couldn’t make any leads stick. Three cops believe they know the man who killed Carol. He’s still out there. But they haven’t been able to prove it. The lead detective calls it the greatest regret of his career.  This six-part podcast from syracuse.com explores the death and life of Carol Ryan and the chilling effect her unsolved murder had on a community. Reporter Katrina Tulloch spent over a year digging into the case, interviewing 25 people including law enforcement, medical professionals, industry experts, witnesses and people who knew Carol.  The podcast outlines how Carol spent the hours leading up to her murder, how first responders bungled the crime scene, the challenges police have faced in trying to find her killer, and how DNA technology could break open the case any day.