FIS 201 – Exam 3 Study Guide (Mohr, WVU)
-no formal education requirements
-certification through IAI and American Criminalistics Society - ANS✔✔ What are the
requirement for a bloodstain pattern analyst?
-contact/collapse
-displacement
-dispersion
-retraction - ANS✔✔ What are the 4 phases of stain creation?
grouping or distribution of bloodstains that indicates the manner in which the pattern was
deposited - ANS✔✔ What is a bloodstain pattern?
-hematocrit
-plasma - ANS✔✔ What two parts is blood compromised of?
Blood droplet his the object and collapses from the bottom up - ANS✔✔ What happens in the
contact/collapse stage of impact?
slight dimples and spines begin to form around the edge of the drop - ANS✔✔ What happens in
the displacement stage of impact?
most of the volume of blood is forced up and out so the spines are extended outward - ANS✔✔
What happens in the dispersion stage of impact?
surface tension pulls the drop flat and the satellites with enough momentum break free -
ANS✔✔ What happens in the retraction stage of impact?
,small droplets of blood broken from the main drop - ANS✔✔ What is satellite spatter?
volume and velocity - ANS✔✔ The size of a blood droplet is dependent on what?
-spatter that is 3mm or greater in diameter
-this type of spatter is usually causes blood to fall under the influence of gravity
-usually forms from weapon cast-off, a person remaining still, walking, or running - ANS✔✔
What is low velocity spatter?
-spatter the is 1-3mm in diameter
-usually forms from blunt force trauma, sharp trauma, or cast-off - ANS✔✔ What is medium
velocity spatter?
-spatter that is less than 1mm in diameter
-appears as a fine spray or misting
-usually forms from gunshot trauma, power tools, an object striking with extreme velocity, or an
explosion - ANS✔✔ What is high velocity spatter?
blood displaced by energetic impact - ANS✔✔ What is impact/forward spatter?
when blood is released or thrown from a blood-bearing object in motion - ANS✔✔ What is a
cast-off pattern?
-speed
-size of object
-number of swings - ANS✔✔ What can you tell from cast-off?
, when blood exits the body under pressure from a breached artery - ANS✔✔ What is a projected
pattern?
blood that is blown out of the mouth, nose, or a would. It is often diluted or contains mucous. -
ANS✔✔ What is expirated blood?
When you draw a straight line through the back of blood stains and where the lines intersect is
the area of convergence - ANS✔✔ What is the area of convergence?
the tail (pointy part) tells which way the bloodstain goes - ANS✔✔ How do you tell the direction
of a blood stain?
an absence of blood - ANS✔✔ What is a void?
-bubble rings
-drips
-saturation - ANS✔✔ What shows that the crime scene has not been disturbed?
-flow
-pattern transfer
-skeletonization
-swipes
-wipes
-insect artifact - ANS✔✔ What can show the order of things that happened at a crime scene?
when blood containing air bubbles dries (shows that the blood is older and not disturbed) -
ANS✔✔ What are bubble rings?
-no formal education requirements
-certification through IAI and American Criminalistics Society - ANS✔✔ What are the
requirement for a bloodstain pattern analyst?
-contact/collapse
-displacement
-dispersion
-retraction - ANS✔✔ What are the 4 phases of stain creation?
grouping or distribution of bloodstains that indicates the manner in which the pattern was
deposited - ANS✔✔ What is a bloodstain pattern?
-hematocrit
-plasma - ANS✔✔ What two parts is blood compromised of?
Blood droplet his the object and collapses from the bottom up - ANS✔✔ What happens in the
contact/collapse stage of impact?
slight dimples and spines begin to form around the edge of the drop - ANS✔✔ What happens in
the displacement stage of impact?
most of the volume of blood is forced up and out so the spines are extended outward - ANS✔✔
What happens in the dispersion stage of impact?
surface tension pulls the drop flat and the satellites with enough momentum break free -
ANS✔✔ What happens in the retraction stage of impact?
,small droplets of blood broken from the main drop - ANS✔✔ What is satellite spatter?
volume and velocity - ANS✔✔ The size of a blood droplet is dependent on what?
-spatter that is 3mm or greater in diameter
-this type of spatter is usually causes blood to fall under the influence of gravity
-usually forms from weapon cast-off, a person remaining still, walking, or running - ANS✔✔
What is low velocity spatter?
-spatter the is 1-3mm in diameter
-usually forms from blunt force trauma, sharp trauma, or cast-off - ANS✔✔ What is medium
velocity spatter?
-spatter that is less than 1mm in diameter
-appears as a fine spray or misting
-usually forms from gunshot trauma, power tools, an object striking with extreme velocity, or an
explosion - ANS✔✔ What is high velocity spatter?
blood displaced by energetic impact - ANS✔✔ What is impact/forward spatter?
when blood is released or thrown from a blood-bearing object in motion - ANS✔✔ What is a
cast-off pattern?
-speed
-size of object
-number of swings - ANS✔✔ What can you tell from cast-off?
, when blood exits the body under pressure from a breached artery - ANS✔✔ What is a projected
pattern?
blood that is blown out of the mouth, nose, or a would. It is often diluted or contains mucous. -
ANS✔✔ What is expirated blood?
When you draw a straight line through the back of blood stains and where the lines intersect is
the area of convergence - ANS✔✔ What is the area of convergence?
the tail (pointy part) tells which way the bloodstain goes - ANS✔✔ How do you tell the direction
of a blood stain?
an absence of blood - ANS✔✔ What is a void?
-bubble rings
-drips
-saturation - ANS✔✔ What shows that the crime scene has not been disturbed?
-flow
-pattern transfer
-skeletonization
-swipes
-wipes
-insect artifact - ANS✔✔ What can show the order of things that happened at a crime scene?
when blood containing air bubbles dries (shows that the blood is older and not disturbed) -
ANS✔✔ What are bubble rings?
