Crime scene processing lays the foundation for further investigation and its success. Crime scene inspection, in many cases, brings crucial evidence and provides primary leads. However, since there is normally a significant interval between a crime is committed, and the investigation starts, the crime scene may lose much of its valuable content. Things get moved, surfaces get wiped or spilled on, etc. Besides, there are things (like poured or splashed liquids) that may not last until they are to be properly inspected by specialists. That is why, for the effective investigation, it is important to take all the necessary crime scene processing measures correctly, and the role of the first responding officer is particularly significant.
The first responders are people whose main responsibility is to secure, preserve, and protect the crime scene. First responders can be police officers as well as paramedics or fire department personnel. Since they are the first people to attend a crime scene, their most immediate concern is to ensure safety by assisting the victim (or victims) and arresting the suspect (suspects). According to Miller and Braswell (2010), the next step is to detain witnesses and make sure they are kept separately.
The reason for preventing witnesses from talking to each other is not to let them affect one another’s impressions and perception of the crime. The less the witnesses interact, the greater the possibility is for the investigators to build an objective picture by comparing the witnesses’ testimonies. Next, the first responding officer is to protect the crime scene for inspection.
Once the crime scene is safe, it is to be preserved. First, it should be enclosed, e.g., by a barrier tape. Hess, Orthmann, and Cho (2016) advise first responders to make the crime scene as big as possible because it can be shrunk at any point, but it cannot be extended once it is set up. Based on surveys, these authors also provide a list of what first responders should and should not do. The first responding officer should establish one single point where the crime scene can be accessed.
Then, the crime scene is examined. Any changes introduced to the scene should be recorded by the first responder and later communicated to investigators. It is important that the first responding officer does not try to put things back where they were. For example, if paramedics had to move a table when transporting a victim, the first responder does not put the table back, but only records that the table has been moved.
However, if there is perishable evidence, like a footprint out in the rain, first responders should try to protect it, e.g., by placing a plastic container over the footprint. What first responding officers should not do is smoke, drink, or eat in the scene because all this is contaminating. Neither should first responders use their phones, trash cans within the scene, or laugh—the latter “just looks unprofessional” (Hess, Orthmann, & Cho, 2016, p. 709). It is also useful to take some pictures of the scene on this stage.
The main goal of the crime scene inspection is to collect physical evidence. Gardner (2012) writes, “Unlike testimonial evidence, physical evidence does not lie” (p. 21). However, physical evidence may be misinterpreted, which is why documenting the context is as important as collecting it. Upon arrival, the crime scene investigator should evaluate the security level and protection of the scene and change something if he or she finds them insufficient.
A so-called “walk-through” (Miller & Braswell, 2010, p. 119) is to be performed to assess if some physical evidence requires immediate action and prepare a preliminary reconstruction theory. Next, crime scene documentation starts. It is an ongoing and the most time-consuming component of the crime scene investigation (Gardner, 2012). Documentation implies describing and depicting every possibly relevant detail. Miller and Braswell (2010) point out four parts of such documentation: taking notes, taking pictures, filming, and sketching. All four should be present, as they are not interchangeable. Finally, the stage of physical evidence collection begins (although the stage of documentation does not stop but continues throughout the crime scene investigation).
Based on the variety of types and characteristics of physical evidence, there is a wide range of ways and tools to collect and preserve it. Priority should be given to fragile and perishable objects. Items must always be packaged separately to prevent cross-contamination, but the connection between them, if present in the scene, should be documented (in photographs, written description, etc.).The main principle of collecting physical evidence is to preserve objects in an adequate state for analysis to establish a particular factual knowledge about the crime scene and what happened in it.
The goal of an investigation is to establish the truth about a crime—who committed it, how, and why. A crime scene if the first place to look for theories in this regard as well as for evidence. To take from the crime scene as many valuable data as it can offer, the first emergency service employees who arrive at it should make sure that it is safe and preserved. Then, investigators should document as much relevant information about the scene as possible and collect physical evidence for further laboratory analyses. This approach is to ensure obtaining accurate factual data from a crime scene.
References
Gardner, R. M. (2012). Practical crime scene processing and investigation. Boca Raton, FL: CRC Press.
Hess, K. M., Orthmann, C. H., & Cho, H. L. (2016). Criminal investigation. Boston, MA: Cengage Learning.
Miller, L. S., & Braswell, M. C. (2010). Crime scene investigation. Amsterdam, Netherlands: Elsevier Science.