Examination of physical pattern evidence
Physical fit, also called direct fit, matching is the simplest, yet, often one of the most persuasive types of evidence that can be obtained. A physical direct and fit match is a match between or among pieces of a randomly fractured, torn, or cut object. The process of recognition is the first step of physical pattern comparison. Direct physical fit and matching is jigsaw fit matching and is applicable to solid materials that break into pieces in a random way. Indirect physical matching is fitting, or attempting to fit, severed, broken, or torn pieces of an item or object together in a way that convincingly demonstrates that the pieces were once part of the same structure. Pattern evidence can be seen as one of the four major categories of physical evidence in terms of the scope of criminalistics. It is usually thought of as physical matching exercises, imprints, striations, shapes and forms, and reconstruction patterns.