Preliminary study of the comparison of inked barefoot impressions with impressions from shoe insoles using a controlled population

Barefoot morphology comparison examines the shapes the weight-bearing areas of a foot make in its impression to try to determine whether a suspect can be excluded as the person who made a crime scene impression or included as someone who could have made the impression. In some cases, an examiner is asked to compare a suspect's barefoot impression with an impression left by a foot on the insole of a shoe. Because of the constriction of the foot caused by the shoe, the comparison is not as straightforward, and the approach to the comparison must be suitably conservative. In this paper, we provide the results of a series of experiments designed to provide some validation for this type of examination. Inked impressions were compared to inked impressions, shoe insoles were compared to shoe insoles, and, most importantly, inked impressions were compared to shoe insoles. The "like versus like" comparison results (undertaken with known inked impressions or known shoe insole impressions) were evaluated against comparisons of inked impressions with corresponding insole impressions. The like versus like comparisons demonstrated better correspondences, and the comparison of inked impressions with shoe insoles demonstrated that the closest correspondence was for impressions made by the same person as opposed to impressions made by different people.