n be determined. Third, the direction and velocity of the impact which caused the stains can be determined. Fourth, analysis can determine the number of blows (or shots) which produced the blood spatters. Fifth, the positions of the victims and the objects used in the crime can be determined. Sixth, analysis can usually determine the movement and directionality of the persons and objects as the blood was being spattered.
Among the more common generalizations which have been disproved in blood spatter analysis is that the size of a blood spot is not a necessarily good indicator of the distance in which the blood dripped from the source. The major influence on the size and edge character of a blood spot is the texture of the target surface. A rough surface will rupture the surface of a blood drop and cause spatter, enlarging the blood spot. Therefore, the size of a blood spot can only be used to determine the distance the blood fell if the target surface has been taken into account. Some researchers have argued that the volume of the blood drop must also be taken into account, saying that there is no "normal drop" volume and that volume can greatly affect the pattern. These researchers point out that volume can almost never be determined at a crime scene.
Similarly, the shape of a blood drop is largely determined by texture
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