Crimes of violence frequently result in  bloodstains and blood spatter being found at the scene. A complete analysis of the blood spatter and stains at the scene , when properly interpreted by a qualified analyst, may be able to answer such questions as:
What was the origin of the bloodstain?

What may have caused the bloodstain or spatter?

What position was the victim in – standing, sitting, lying down when shot or struck by a blow that caused the blood spatter?

What was the directionality of the energy (gun shot, blunt force blow, stabbing) of the energy that caused the blood spatter?

What was the movement of the victim and/or assailant during the assault? After the assault?

How many blows or gunshot wounds did the victim receive?

The case for analysis: Prosecuting & Police Agencies

Bloodstain and spatter analysis is just one tool that a police department or a prosecuting agency can use to enhance and further substantiate blood evidence found at a crime scene. When properly studied and analyzed, bloodstain evidence can aid in the reconstruction of the crime scene, including the position and movements of the victim and assailant. Further, it can be a useful tool to preclude a specific action as being the only mechanism that produced the bloodstain or spatter pattern. Accordingly, such evidence can be used to disprove a suspect’s account or explanation of  the presence of blood on his or her person or clothing., or any other location where it should not normally been found.

Bloodstain analysis is not only a tool of the prosecution. Analysis of the blood evidence is frequently used to provide legitimate substantiation of a defendant’s version of events. A defendant claims self-defense in a violent encounter., but verifiable proof is needed. A proper analysis of the bloodstain evidence might provide such evidence.                               

Obviously, an inspection of the actual crime scene concurrent with the responding law enforcement agency is the most desirable time to conduct an analysis of the bloodstains and spatters present. Blood on and around the body of the victim can be properly analyzed, and other evidence found by police investigators can be considered in the overall analysis at the scene. Contemporaneous analysis also permits the analyst to secure relevant photographic documentation for further study.

Otherwise, access to all tangible evidence, photographs and reports obtainable through discovery are required.