The Role of Evidence
Many investigators subscribe to the practice of “collect everything” from the crime scene, while others collect little or no evidence and rely upon the
witnesses. The former tends to lead to the “tag and bag” mentality while the latter ignores the value of evidence in an investigation. The goal of evidence collection and reconstruction is the identification,
apprehension, prosecution, and ultimately the conviction of the true perpetrator of a specific offense. To do this, the scene must be objectively viewed from its first encounter to its court presentation. Every effort must
be made to exonerate an innocent suspect and to reduce the number of possible crime scene reconstructions to those which are the most logical. Physical evidence is one way of providing objective information to the
investigation of the crime and the ultimate reconstruction of the actions of the participants. If an item is collected and not used in establishing the who, how, why, when, or what during some phase of the criminal
justice process, then that item is simply "property" requiring storage and not evidence useful in a court of law.
We usually recognize an object as evidence when its value to a case is clear and significant. The difficult part is to sort the evidence from property, then to
further sort the more discriminating evidence from the less valuable evidence. To establish the “evidence value” of property at the scene, the investigator must begin with a theory of what has transpired. This
theory should be integrated with the investigators knowledge of what “clues” can be learned through “common sense” evaluations at the scene, or from scientific analysis.
And from the photography section…
Photographing the Scene
The camera is at the scene to record the appearance of objects and their relative positions so that others not present at the scene can obtain knowledge of
evidence and the crime setting.
Duplicate the Eye
To do the photographic job properly, the camera must take pictures which provide the person looking them the ability to orient any object to its surroundings. The
photographer should use the camera to mimic the process used by each of us to orient an object to our surroundings. First we get the widest view possible, then move in closer. The investigator who examines the crime
scene performs the simple operation of looking at all objects and building a “roadmap” of relationships. Those of greater interest to the investigator loom larger in his mind. This is the same process that
the jury must be able to perform; however they will usually use the photographs to get sense of the real “three dimensional” crime scene.
The camera, like the eye, should scan an area to show the relative positions of objects in an “overview” photograph. This perspective information is used to orient the subsequent viewers
to the overall scene. Then the photographer’s eye and camera select a reduced field of view providing an “approach” picture. As an object is evaluated at nearer distances, the camera captures “close-up
photographs.” If any of these steps in photography are eliminated, the viewer of the pictures will become disoriented and confused, perhaps not recognizing what or where an object really is. Photography,
regardless of the media used, must follow this technique to keep the subsequent viewer oriented to the scene, without a narrative explanation.
Where to Start
Photography at the crime scene should begin on the outside and work its way in. It should be closely integrated with the processing methodology and always proceed by
taking overview, approach, and then close-up photographs prior to collecting an item. Consider the following steps:
Photographing the scene should be initiated by standing back and taking overview photos to show total spatial relationships and perspectives.
As an item becomes the focus of interest, an approach photo should then be taken to illustrate finer details of the object and its surroundings being sure to include landmarks which were visible in
the overview photographs.
When attention is drawn to a certain item, close-up photos should be taken which show every detail of the object. One set of overview and approach photos often will support more than one item
recorded by its close-up photograph.