lec 9 bloodstains Flashcards
crime-scene reconstruction
The method used to support a
likely sequence of events at a crime
scene by the observation and
evaluation of physical evidence and
statements made by individuals
involved with the incident.
satellite stain
A smaller bloodstain that originated during the formation of the
parent stain as a result of blood
impacting a surface.
angle of impact
The angle (alpha), relative to the
plane of a target, at which a blood
drop strikes the target.
spatter pattern
A bloodstain resulting from an
airborne blood drop created when
external force is applied to liquid
blood.
impact spatter
A bloodstain pattern resulting from
an object striking liquid blood.
forward spatter
A bloodstain pattern resulting from
blood drops that can be produced
when a projectile creates an exit
wound.
backspatter
A bloodstain pattern resulting
from blood drops that can be produced when a projectile creates an
entrance wound.
area of convergence
The space in two dimensions to
which the directionalities of spatter
stains can be retraced to determine
the location of the spatter-producing
event.
area of origin
The space in three dimensions to
which the trajectories of spatter
can be utilized to determine the
location of the spatter-producing
event.
cast-off
A bloodstain pattern that is created
when blood is flung from a bloodbearing object in motion onto a
surface.
projected pattern
A bloodstain pattern resulting
from the ejection of blood under
hydraulic pressure, typically from a
breach in the circulatory system.
expiration pattern
A bloodstain pattern resulting from
blood forced by airflow out of the
nose, mouth, or a wound.
void
An absence of blood in an otherwise continuous bloodstain or
bloodstain pattern.
transfer stain
A bloodstain resulting from contact
between a blood-bearing surface
and another surface.
flow
A bloodstain resulting from the
movement of a volume of blood on
a surface due to gravity or movement of the target.
perimeter stain
An altered stain consisting of its
edge characteristics, the central
area having been partially or
entirely removed.
drip trail pattern
A bloodstain pattern resulting from
a liquid that dripped into another
liquid, at least one of which was
blood.
the intersection of straight lines through the long axis of several individual bloodstains in an impact splatter pattern illustrates the ______ of the pattern
area of convergence
the pointed end of a bloodstain always faces
its direction of travel
the amount of splatter from a blood droplet falling on a hard, nonporous surface is _______ that of a drop of blood of equal size, falling from the same distance onto a softer, porous surface
less than
crime-scene reconstruction requires piecing together…?
-accounts given by witnesses and suspects
-input from medical examiner
-the story told by evidence recovered at the crime scene
when an object blocs the deposition of blood spatter onto a target surface or object the result is a…?
void pattern
physical evidence that can be used to aid in a crime-scene reconstruction includes..?
a. blood spatter
b. gunshot residue
c. glass fragments
d. all of the above
d. all of the above
the most common type of bloodstain pattern found at a crime scene is..?
impact splatter
drops propelled from a blunt surface will be larger and the pattern will be
a. narrow
b. wide
c. linear
d. thin
b. wide
what is created when an object with blood on it touches one that does not have blood on it?
transfer pattern
at the crime scene, the string method is used to find the ____ of an impact splatter pattern
area of origin
