had during her earlier years. >> 17-year-old shannon touchet had worked on ron shaw's home and would have known about the safe hidden in the master bathroom closet. investigators went to shannon's home. he wasn't there, but his mother was, and she was very helpful. >> she reported to us that she had found some bullets and a black bag, a black bag that she recalled had at one time also contained ski masks and drugs. >> police found the bag in shannon's bedroom. the drugs and ski masks were gone, but they did find 13 unfired .38-caliber bullets. investigators wondered whether these bullets matched the ones that killed ron shaw. firearms expert chris henderson examined the knurls on the fatal bullets. knurls are the ridge-like protrusions that hold the lubrication needed to fire them. henderson then compared those knurls with the knurls on the bullets found in shannon touchet's bag. >> we had the same number of knurls, same width, and those knurls looked kind of like railroad tracks going around the outer surface of that bullet. all the physical characteristics, everything we could phys