 
After initial crime scene photography
and documentation have been completed,
the crime scene investigator places
reference scales near the blood spatter
and selects the individual stains for
analysis.
The investigator draws a line extending
along the path, or length axis of each
selected stain. The area where these
lines intersect is called the area of
convergence, which indicates the
approximate height of the incident that
produced bloodshed.
The examiner uses a loop to measure the
length and width of each stain, then
calculates the angle at which the
droplet impacted the surface. Once the
investigator knows the area of
convergence and impact angles for a
group of stains, the stringing process
begins. The investigator attaches one end
of the string to each stain location at
the point where the blood drop contacted
the surface. Then, using a protractor
pulls the string along the angle of
impact, and secures it to something
stable. Once several strings are in place,
the area of origin becomes visible. This
complex, time-consuming process creates a
three-dimensional model that indicates
where the victim was located at the time
of the event.
 
