Chapter 4 Powerpoint

Take the item when you can (floor; door; car; portion of wall)

Documentation

Individualization Patterns and Reconstruction Patterns

pattern evidence that can potentially uniquely associate the pattern with the item or person responsible for producing it (fingerprints; palm prints; handwriting; tool marks)

pattern evidence useful in reconstructing past events; it is not only the evidence that is important, but how it got there and became evidence. (blood splatter; glass fracture; tire and skid mark; clothing; fire burn; wound injury)

crime scene patterns

a grouping or distribution of bloodstains that indicate through regular or repetitive form or order, or arrangement, the manny in which the pattern was deposited (SWGSTAIN)

pattern of dried blood on a surface resulting from an event that causes blood to exit the body and/or be broken into particles and distributed by force (BOOK)

Scientific Working Group on Blood Pattern Analysis; made up of blood pattern analysts (BPAS) from North America, Europe, New Zealand, and Australia; determine recommend guidelines and terminology for use by all BPAs

• it follows standard physical laws 2. makeup - viscosity, density, and other physical properties

a deposit of blood on a surface

the surface onto which the blood has been deposited

characteristic of a bloodstain that indicates the direction of blood was moving at the time of deposition

acute angle relative to the plane of a target at which a blood drop strikes a target

bloodstain resulting from a falling drop due to gravity

bloodstain pattern resulting from movement of a source of drip stains between two points

bloodstain resulting from an accumulation of blood on the surface

bloodstain pattern resulting from a volume of liquid blood that falls or spills onto a surface

blood stain pattern resulting from the transfer of blood from a blood bearing surface onto another surface, with characteristics that indicate relative motion between the two surfaces

altered blood stain pattern resulting from an object moving through a pre existing wet bloodstain

• low velocity • medium velocity • high velocity

blood stain pattern formed cased by falling blood; gravity is the only acting force on the blood; typically drip patterns

bloodstain pattern formed when moderate force from an object acts upon a pooled area of blood and causes the blood to “scatter” in all directions; drops are smaller and greater in number than with low velocity bloodstain pattern

blood stain pattern that results from extreme force acting upon a blood source; drops are much smaller (like aerosol spray) and more numerous vs. Medium velocity)