crime scene search assignment

                A ‘walk-through’ is the initial survey of the crime scene carried out by the lead investigator to gain an overview of the scene in order to formulate a plan for processing the scene.  You would perform a ‘walk-through’ to get a sense of ‘feeling’ for what you need to look for and gives a ‘starting point’ to collecting the evidence.  A command center is a secure site outside the boundaries of a crime scene where equipment is stored, tasks are assigned, and communication occurs. It is good to have one because the lead investigator assigns tasks after the initial ‘walk through’. The tasks include locating possible evidence, assessing the evidence, processing the evidence (fingerprints, foot impressions, ore tire impressions..) and photographing the scene. The command center is like the brain of an investigation and it is the center for activities that need doing.  The basic reason/necessity to search the crime scene is to locate evidence and process the evidence that is acquired. There are five types of search patterns discussed in our books. They are strip/line search, grid search, spiral search, wheel/ray search, and quadrant/zone search.  There are patterns that are better than others, but some depend on the size of the crime scene. If you have a large area to cover like a body of water or the Florida everglades an aerial search would be most adequate. The strip search pattern is best used in scenes where the boundaries are well established because the boundaries indicate the beginning and end of the search lines. If the boundary is incorrectly chosen, important evidence may remain undiscovered outside the search area. The grid search pattern is very thorough, but needs to have well established boundaries. The spiral pattern is often a difficult one because a searcher may not always make a perfect spiral and important evidence may tend to be missed. The wheel/ray search pattern is not preferred because the areas between the rays are not searched and evidence will likely be missed. The quadrant search is best suited to cover a large area. I believe you can do more than one type because if you have blood inside a house that has a huge farm and there are blood trails that lead outside to say a barn, you must perform an inside search, which will most likely be a line or strip search pattern, and then a quadrant search outside for more evidence.  A visual ‘sweep’ is conducted at the end of the investigation and that is like ‘re-searching’ what has already been searched by teams just to make sure nothing was missed.