Physical evidence seized at the crime scene normally requires some degree of processing or comparative analysis. Processing may include items such as developing fingerprints; conducting chemical drug, explosives, and metallurgy analysis; gathering toxicology reports from autopsies; and other forms of identification of evidence seized. Another form of processing physical evidence is to match patterns and fractures to determine whether an impression was made from an object match (e.g., tool marks, bullet markings, footwear impressions, tire impressions, and fingerprints) or whether two broken items once formed one item.

There are two categories of evidence. One is the physical evidence that bears class characteristics, such as brand, model, color, size, caliber, and so on. This means that the item(s) being examined falls into a category of items that are similar. This is a useful tool for eliminating evidence as significant. The category known as individual characteristics is one where an item of evidence is unique and no other item of evidence would bear the same markings or identifying features.

Discuss the following in your main post:

• Explain the concept of evidence that contains individual characteristics. Provide 2 examples of evidence with individual characteristics.
• Explain the concept of evidence that contains class characteristics. Provide 2 examples of evidence with class characteristics.
• State the product rule, and explain how it applies to the comparison of physical evidence. How do inductive and deductive logic apply to physical evidence?