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solving crimes with physics
A proper analysis of blood-spatter patterns can yield a surprising
amount of information about the crime. Among the easily identi-
fied facts that can be determined by examining blood-spatter pat-
terns are the positions of the victim, assailant, and objects at the
scene. In addition, the type of weapon used to cause the spatter
can sometimes be determined by looking at the wound and the
sorts of spatter present. Multiple spatters can indicate the number
of blows, shots, stabs, or other attacks that occurred. The move-
ment and direction of victim and assailant after bloodshed began
is usually readily apparent. Among the most crucial evidence is the
ability to determine what events occurred and in what sequence
they occurred. This can be vital to a prosecution.
In other words, the satellite droplets will be found farther along the line
of travel than the parent droplet. If a line were drawn through the satellite
spatters back through the center of the parent droplet, it would point in the
direction from where the blood originated. Image 3 is a depiction of what
a blood droplet moving as it hit a surface would look like. The elongated
spine at the end of the droplet indicates the direction the droplet was mov-
ing when it impacted the surface.
In addition to direction of travel, an investigator can usually determine
the amount of energy behind the droplets by looking at their overall size.
Generally, small droplets are the result of higher energy projecting them
outward from their source. This information is particularly important in the
case of violent attacks; determining the amount of energy can indicate how
hard a victim was hit. It is usually very difficult for a suspect to argue he
