Investigators approach a crime scene using different methods of collecting evidence. Many of these methods are similar to methods used for searches. For example, some begin collecting evidence at the entrance and work in a pattern toward the exit. Some work in a spiral from the center (or the body if there is one) and work toward the outer edge, and some employ a grid pattern. No matter which method you prefer, be sure that you use one.

In years past, it was procedure in many departments for evidence to be stored in plastics — plastic containers and plastic bags. A good deal of crucial material was rendered useless by sitting in plastics, sometimes for years. It's now known that paper and metal are the preferred storage materials for evidence. Blood drawn from suspects is placed in vials with different colors.

The scientific examination of this type of evidence falls under the heading of forensics. The two major branches of forensics are Criminalistics and Forensic Medicine. Those trained in these branches are responsible for turning physical clues into evidence. The following list shows what each branch is responsible for examining:

Criminalistics Examines: