Examination of Crime Scene Impressions with Known Footwear
This chapter discusses considerations that arise during the comparison and evaluation of footwear evidence. The term best evidence refers to the original scene impression or, if that no longer exists, the closest evidence to that original impression. Repetitive shoe impressions will have slight distinctions between them. These are known as "variations" and they are both normal and unavoidable. Reproducibility is the ability to reproduce something over and over again. Repeatability is the degree of agreement between those reproductions. The distinction between mold damage and outsole damage should be clearly understood. Scratches or dings in a metal mold or to a calender roller become filled with the outsole compound during molding and result in raised areas on outsole or outsole material. The manufactured class characteristics of the outsole design and the physical size of that outsole design should always be evaluated first. Determining how many shoes of a particular shoe outsole design potentially exist involves additional considerations.