Very few articles or publications relating to crime scene investigations and evidence recovery are actually written by those investigators working in the field. The work, although very basic, is time consuming and tedious at best. The duties consist of detection, collection, preservation, packaging, transportation, and documentation of physical evidence left at a crime scene. Although the duties and job description may vary from departments and agencies, the basic methods and techniques for recovering the evidence are similar. The important chain of custody for the evidence usually starts with the crime scene investigator (CSI).
The CSI is viewed as a forensic specialist in the scientific community. Our specialty is considered the professional systematic approach to the processing of a crime scene. We need to have a basic working knowledge and understanding in a large diverse field of subjects. To assure consistency and proficiency in the field requires extensive study, training, and on the job experience. We must be well versed in all areas of scene recognition, scene documentation, and evidence recovery. A general knowledge of our labs procedures and what analysis may be preformed in the lab as well as consistency in marking, tagging, handling, and packaging of items of evidence is needed.
There are several factors needed for our success. The foundation of success starts with basic skills. Many people have suggested that the three keys to success are knowledge, skill, and attitude. This is very true. Attitude is a most important factor for success in anything that we set out to accomplish. The attitude represents the will of an individual. If an individual has the will or desire to do something then the knowledge and skill in any task can be developed. Two other factors for success are communications and teamwork. The teamwork and communications starts in the office and is carried out into the field. The importance of communicating and sharing information not only in our own departments and agencies but also with our peers in the forensic field can never be overstressed.
The value of the evidence found at a crime scene starts with the first person arriving at the scene. The success of the entire investigation hinges on that first person being able to properly identify and secure the scene for processing. The value of the evidence continues as each individual involved in the chain of custody, from the collection of the evidence to its completed analysis.
Formulating a plan of action for the systematic approach to the scene investigation begins at the time of the initial request for service. By obtaining as much information as possible the CSI can determine his resources as to any assistance that might be needed as well as any special equipment that may need to be assembled before responding to the scene. It is at this point that a lead CSI should be selected for the investigation. In our department we use a rotation system to determine who will be designated as the lead CSI on a given request. The plan may necessitate several revisions from the time of receiving the request to the completion of the scene processing. Most CSI’s are very flexible and adaptable to their environments and working conditions.
After arriving at the scene a walk through of the scene will allow for systems and plans to be put into place. At this point it is suggested that everyone involved in the investigation be briefed as to what plan needs to be in place. Major scenes (indoor or outdoor) need at least 2 people to sufficiently process the scene. For extensive scenes the luxury of 3 or 4 CSI’s is suggested. During the progression of the scene processing continual briefing and communications between all parties involved in the investigation will allow for effective and organized results. A good investigator will not limit his resources or compromise his task with time restraints.
An area that is often overlooked and has a reasonable chance for evidence is the pathways to and from the crime scene. These areas are often overlooked due to the traffic created by first responders, medical aides, and various other onlookers. An aggressive effort by the CSI may yield valuable evidence from these areas. After the initial walk through It is suggest that an area be developed as a designated work area. A folding table or counter top is suitable. This area allows for a storage area for needed equipment, an area to brief all individuals involved in the scene investigation, and can even be used as a break area for needed comfort.
After the scene processing has been completed, all evidence has been collected, and all equipment has been repacked a final walk through of the scene is suggested. This assures that all of the evidence at the scene has been collected and that no equipment has been left behind. To complete the task a final briefing should then take place allowing everyone involved in the investigation to be aware of what has been completed.
The final results of a proper systematic approach to Crime Scene Investigations is the ability of others, after viewing your completed work, to reconstruct the incidents and of course your courtroom presentation.