Chapter 7 : Environmental Samples as Evidence: Labeling and Documentation at a Crime Scene

Abstract:

This chapter provides a detailed examination of the sample documentation process, highlighting the importance of each step for criminal investigations. For the criminal sampling process, knowing that something needs to be documented is important but understanding why something needs to be documented is critical. There are generally three types of samples that require extensive documentation in the aftermath of a biological release. The first type of sample is the public health and safety sample. The second type of sample is the environmental sample. The analysis of these samples helps guide those responsible for the decontamination of a specific area and the restoration of the environment. The third type of sample is the criminal sample. Duct tape consists of cloth/cotton fabric coated with polyethylene. When the duct tape is torn, cotton fibers may become airborne. Should these airborne particles come into contact with protective clothing (e.g., gloves or sleeves), sampling tools, or sampling containers, they may contaminate the item with foreign DNA. If footprints are found within the contaminated zone, it may be difficult to differentiate between those made by a suspect and those created by emergency responders. The documentation supporting these activities must also be collected and securely stored in a central location at the crime scene. At the completion of these activities, the crime scene investigation team should conduct a postsearch briefing. In summary, the importance of documentation throughout the sampling process cannot be stressed enough.