What is the primary purpose of class characteristics in forensic evidence?

The primary purpose of class characteristics in forensic evidence is to narrow down a group of items. Class characteristics are shared by a group of objects or materials and can help forensic analysts categorize evidence based on common traits. For example, the tread pattern on a shoe can be associated with a specific brand and model, thus linking it to a group of shoes rather than identifying a unique shoe worn by a specific individual.

This process is critical in forensic investigations, as it helps investigators focus their efforts on a smaller subset of evidence, making it more manageable to analyze and potentially leading to a more accurate pinpointing of individuals later in the investigation through additional methods, such as comparing unique individual characteristics. Unlike individual characteristics, which can uniquely identify a single source, class characteristics serve as a way to identify characteristics that multiple items share, which can aid in narrowing down suspects or sources in a broader context.