footprint in a hamburger bun next to christina's body. investigators believed it was made by the killer as he fled the scene. in order to verify their work, iowa investigators took the bun and photographs to gene czarnicki, a certified print examiner at the dci crime lab in des moines, iowa. czarnicki not only confirmed this was a right foot in the soft bread but found enough clear ridge detail to convince him that it was the footprint of carlos robinson. >> i think if the bun was in a dry or stale condition, the print may have not been reproduced. we were quite fortunate in that the bun appears to have been fresh when he stepped on it. >> this proved that the only evidence at the crime scene was carlos robinson's. investigators believe christina