Hair as Evidence What can it do for us?
Why Hair? One of the most common pieces of evidence Burned hair Hair from a child is examined for drugs
History of Hair Analysis * Alfred Swaine Taylor and Thomas Stevenson *1883 *forensic science text that included a chapter on hair
History of Hair Analysis Victor Balthazard, professor of forensic medicine at the Sorbonne, with Marcelle Lambert (1910) First comprehensive hair study, Le poil de l'homme et des animaux. Rabbit hair Bat hair Badger hair
History of Hair Analysis 1910- Murder of Germaine Bichon Rosella Rousseau confessed only after confronted with hair as evidence. Hair found under Bichon’s fingernails. What are the possible limitations of using hair as evidence in a crime investigation?
For Discussion What are the possible advantages of using hair evidence? What reasons might have prevented investigators from using hair in investigations before 1910? What kinds of technology advances have made it possible for investigators to use hair as evidence?
For Discussion What are the possible advantages of using hair evidence? What reasons might have prevented investigators from using hair in investigations before 1910? What kinds of technology advances have made it possible for investigators to use harir as evidence?
For Discussion What are the possible advantages of using hair evidence? What reasons might have prevented investigators from using hair in investigations before 1910? What kinds of technology advances have made it possible for investigators to use hair as evidence?
Comparison Microscope Dr. Sydney Smith, in 1934, first used a comparison microscope to analysis hairs side by side. Helped to solve murder case.
Neutron Activation Analysis Bombard sample with neutrons Sample spontaneously emits energy Measure the energy emitted to determine the presence and amounts of more than 60 elements.
DNA fingerprinting DNA from root or other cells stuck to follicle
What is hair? And who has it?
Who has hair?
Why do we have hair? ?????????
Why do mammals have hair? 1. Warmth 2. Decrease friction 3. Protect against sunlight 4. Act as a sense organ
Skin and Hair Structure
Skin and Hair Structure
Skin and hair Structure
Hair Structure
Hair Structure Compare hair to a pencil.
Three Parts of Hair Composed of: Cuticle— overlapping scales; protects cortex Cortex— made of keratin (protein which makes hair strong and elastic) and imbedded with pigment; changes with perms, dyes, etc. Medulla—innermost layer; purpose unknown
Cuticle Patterns 23
Cuticle Patterns scales appear like stacked cups (ex. Mouse) Coronal (crown like)- scales appear like stacked cups (ex. Mouse) 24
Cuticle Patterns Spinous (petal -like) triangular shaped scales, often protrude from the shaft (ex. cat)
Cuticle Patterns Imbricate- Flattened, overlapping scales (e.g.human)
Hair Scales point to end of hair. The end of the hair is the oldest end. Why is this important?
Medulla Pattern Description Diagram Continuous One unbroken line of color Interrupted (Intermittent) Pigmented line broken at regular intervals Fragmented or Segmented Pigmented line unevenly spaced Solid Pigmented area filling both the medulla and the cortex None No separate pigmentation in the medulla