The suspect, a handyman, claimed he had not been in the house for 6 months: According to the victim's friends, she mopped the floor frequently. Eight tiles were cleaned and numbered, and a latent palm print was placed on each tile. At random intervals over a period of one year, a tile was selected and examined with reflective lighting, with any observations of latent print residue recorded. One side of the tile was then wiped using tap water, allowed to air dry, and processed using a fiberglass fingerprint brush and black powder. Findings were consistent throughout the course of the study. Latent print evidence remained constant and viable for one year; in fact, the longer a print remained on the tile under controlled temperature and humidity conditions, the more durable it appeared to become.