24 terms

BLOOD SPATTER - Bertino Chapter 8 Forensics, Hug HS

Vocabulary used to describe blood spatter
Angle of Impact
The acute angle formed between the direction of a blood drop and the plane of the surface it strikes.
Arterial Spurting
Bloodstain pattern resulting from blood exiting the body under pressure from a breached artery
Evidence that liquid blood has come into contact with a surface
Blood Spatter Analysis
A field of forensic science that deals with the physical properties of blood and the patterns produced under different conditions as a result of carious forces applied to the source of blood
Cast-Off Pattern
A blood pattern created when blood is released or thrown from a moving blood-bearing object like a knife or hammer
The direction the blood was traveling when it hit the target surface; investigators can usually establish directionality of a blood drop's flight from the geometric shape of its blood stain.
Contact Stain
Blood deposited from direct contact between two surfaces at least one of which is bloody
Expirated Blood
Blood that is blown out of the nose, mouth, or a wound as a result of air pressure or air flow, which is the propelling force.
Back Spatter
blood directed back toward the source of energy or force that caused the spatter
Forward Spatter
Blood that travels in the same direction as the source of energy or force that caused the spatter.
High - Velocity Impact Spatter
A bloodstain pattern caused by a high speed impact or force to a blood source such as that produced by gunshot, velocity may be 100 ft/sec, generally forming drops less than 1 mm.
Low-Velocity Impact Spatter
Blood spatter with droplet size greater than 4mm caused by blunt object impact or dripping.
Medium- Velocity Impact Spatter
A blood stain with droplets of size 1-4mm caused by beatings or stabbings.
Elisa Test
Confirmatory Test for Blood (Enzyme Linked Immunosorbent Assay) involves an antibody-protein reaction similar to blood typing that confirms the substance tested is human blood.
Shadowing or Void
Area devoid of blood spatter because an object was in front of the wall or floor during the injury but has been moved since.
Point of Origin
A three-dimensional view formed using lines of convergence and angles of impact of at least two different drops of blood to identify the source and location of blood spatter
Area of Convergence
The approximate location of a blood source can be determined if there are at least two drops of blood. Straight lines are drawn down the longitudinal axis and where the lines intersect indicate the 2D location of the injury.
When blood overcomes cohesion and separates out from the main droplet of blood
also called spikes. Elongated extensions attached to a drop of blood due to striking a porous surface and the adhesive properties of blood
Adhesive force
blood molecules are attracted to other surfaces and unlike substances
Cohesive force
blood molecules are attracted to each other, so blood tends to stick together when it falls
transfer pattern
a bloodstain pattern created when a wet, bloody surface comes in contact with a second surface
object moves through partially dried blood with a lateral motion, altering its appearance
blood is a mixture which separates and changes appearance over time as it dries. The appearance can indicate how long it has been outside the body.

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