Science of Crime Scenes Chapter 7.1 Science of Crime Scenes

An Archaeological Approach to CSR Science of Crime Scenes

Science of Crime Scenes Careful destruction The goal of an archaeological excavation is to carefully collect artifacts and record all the available information about a prehistoric or historic site of human activity. The goal of reconstructing a crime scene is to carefully collect evidence and record relevant information about a past crime. Both of these processes involve “careful destruction”: They are one-way approaches that deconstruct a contextual location for its later reconstruction Science of Crime Scenes

Transforms: A baseball bat as a weapon C-transforms, cultural formation processes for those instigated by humans Criminal use Fractures in the victim’s skull Production Lacquer on the surface of the bat Shape of the bat Normal use Fingerprints on the bat’s handle (although this could be from criminal use as well) N-transforms for those that occur in nature Drying and decomposition of the blood on the bat Insect activity, drawn by the blood on the bat Science of Crime Scenes

Useful archaeological terms datum, a fixed reference point for all three-dimensional measurements At a crime scene, the datum should be something permanent, or nearly so, like the corner of a room, a tree, or a post. If no datum easily suggests itself, an artificial one, such as a post, nail, or mark, can be made artifact is a human-made or modified portable object feature is a non-portable artifact provenience is the origin and derivation of an item in three- dimensional space, in relation to a datum and other items Science of Crime Scenes

USGS survey marker: A type of datum Science of Crime Scenes

Science of Crime Scenes Time and Space Like other historical science, forensic science employs one of the basic laws of history, which was developed by geologists, that of superimposition Contemporary activities take place horizontally in space Changes in activities occur vertically through time Broadly, the law of superimposition states that newer vertical layers lay on top of the older, lower ones In a crime scene, a body laying on top of a weapon means the weapon was positioned before the body, that is, it is “older” in placement than the body Science of Crime Scenes

Science of Crime Scenes Sidling Hill, Maryland Science of Crime Scenes