by Daryl W. Clemens
Crime Scene Reconstruction- The use of scientific methods, physical evidence, deductive reasoning and their interrelationships to gain explicit knowledge of the series of events that surround the commission of a crime.
-Association for Crime Scene Reconstruction, The Scene, 4(1), Jan 1997, p. 2.
Criminal Profiling- The application of psychological theory to the analysis and reconstruction of the forensic evidence that relates to an offender’s crime scenes, victims and behaviors.
- Turvey, B., “CP101: An Introduction to Criminal Profiling”, Online Course,
http://www.corpus-delicti.com, May 1997.
While both of these activities may appear to be similar and are in fact related, it is important to note that they are not the same. The difference between the two is most easily understood by looking at which questions about the crime they attempt to answer.1,2,3,4 Crime Scene Reconstruction looks at the physical evidence and attempts to determine “What happened?” and “How did it happen?”.5,6 Criminal Profiling looks at the physical evidence and the reconstruction and attempts to determine “Why may this have happened?” and “What does that tell us about Who may have done it?”.7 It is important to keep in mind that only those directly involved in the crime know for sure what happened and why, and they may be unable or unwilling to say. 8,9
Why is it important to reconstruct the crime prior to profiling the offender? The answer is simple; until you know what happened, and how it happened (at least as much as possible), you have no basis for attempting to determine why and who.
This paper is intended as an overview of the types of reconstruction which may be possible and is not all inclusive (the number and types of things that may be reconstructed is like types of physical evidence- nearly limitless). For more specific information check the references or contact an expert in the field in question.
Types of Reconstruction
(Lee, pp. 192-3, lists 5 categories of reconstruction; one deals only with the amount of reconstruction done, and another lists several activities including criminal profiling which are not truly reconstruction).10
- Specific Incident Reconstruction (Traffic Accident, Homicide, Bombing, etc.).
- Specific Event Reconstruction (Sequence, Direction, Condition, Relation, Identity).
- Specific Physical Evidence Reconstruction (Firearms, Blood, Glass etc.).
In any given scene it may be possible to do a total or only partial reconstruction, and the reconstruction may use more than one technique (i.e. both trajectory and blood stain pattern reconstruction to locate the position of the victim).11 Some scenes lend themselves to reconstruction better than others. Traffic accidents are common scenes to reconstruct and often can be thoroughly reconstructed. Vehicles are rather massive objects that obey the laws of motion and often leave a wealth of physical evidence behind before, during and after an accident. It may be possible to show the entire sequence of events from the time the vehicles first enter the area of the accident until they come to rest following the accident.12,13,14
Scenes involving the movement of people are more difficult. While it may be possible to say where a person was in the scene at several points in time, the manner in which they moved in the scene cannot be reconstructed. People may move slowly, quickly, hesitantly, jump up and down, run, skip, fall down, etc. all without leaving any particular trace behind. That said, there are of course the odd cases where the amount and type of physical evidence does allow the paths of the participants to be tracked with some accuracy; however, the vagaries of facial expression, gestures, and body language are simply impossible to reconstruct at all.15,16
Below are some examples of the types of information which reconstruction may provide, again, this is not an all inclusive list. Some items also appear in more than one category, and it may be possible to use information from several areas to complete or validate the final reconstruction.