after 10 years in prison wassim decker was a free man.pect in the murder of carmen smith and the stabbing of her son, nick. >> he was still terrorizing you in some ways. >> just the fact that he was out was kind of terrorizing. >> he is that character in those horror movies. he's like your worst nightmare. >> after his release decker got a job and moved to suburban atlanta. he was a free man and enjoying life. here he is skydiving and loving it. decker's freedom called homicide detective jon doss. the carmen smith murder was now officially a cold case. to dos decker was the one who got away. does a case like this hunt a police department? >> absolutely. because these cases go home with you. in your mind. >> four years dos couldn't do anything about it. and then just by chance he was sent to a dna training seminar in 2008. a random assignment that would change everything. >> back in the mid-90s very, very little at all could be done with the hair, except to say the color of the hair. now when there's any tissue from the root on the here wh