What can it do for us?. One of the most common pieces of evidence Burned hair Hair from a child is...

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Hair as EvidenceWhat can it do for us?

One of the most common pieces of evidence

Why Hair?

Burned hair

Hair from a child is examined for drugs

1847- Duchess of Praeslin murdered by her husband

Husband committed suicide before trial Consequently led to collapse of the

monarchy

History of Hair Analysis

1889- L’Affaire Gouffe

Lacksagne identifieded a rotted body by matching hair color (as well as height, weight, teeth)

Previous attempts to use hair were insufficient- little research on hair

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.

History of Hair Analysis

Badger hairBat hair

Rabbit hair

1910- Murder of Germaine Bichon Rosella Rousseau confessed only after

confronted with hair as evidence. Hair found under Bichon’s fingernails.

History of Hair Analysis

Dr. Sydney Smith- 1934, first use to analyze hairs side by side. Helped to solve murder case.

Comparison Microscope

Originally invented and usedfor ballistics.

Comparison Microscope

Bombard sample with neutrons Sample spontaneously emits energy Measure the energy emitted to determine

the presence and amounts of more than 60 elements.

Neutron Activation Analysis

DNA fingerprinting DNA from root or other cells stuck to follicle

What are the possible limitations of using hair as evidence in a crime investigation?

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 limitations of using hair as evidence in a crime investigation?

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 limitations of using hair as evidence in a crime investigation?

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 limitations of using hair as evidence in a crime investigation?

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 is hair?And who has it?

Who has hair?

?????????

Why do we have hair?

1. Warmth2. Decrease friction3. Protect against sunlight4. Act as a sense organ

Why do mammals have hair?

Skin and Hair Structure

Skin and Hair Structure

Skin and hair Structure

Hair Structure

Hair Structure

Compare hair to a pencil.

Composed of:Cuticle— overlapping

scales; protects cortex

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.

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

Three Parts of Hair

Cuticle Patterns

30

Coronal (crown like)-

scales appear like stacked cups (ex. Mouse)

Cuticle Patterns

31

Cuticle Patterns

Spinous (petal -like)–triangular shaped

scales, often protrude from the shaft (ex. cat)

Imbricate- Flattened, overlapping scales(e.g.human)

Cuticle Patterns

Scales point to end of hair. The end of the hair is the oldest end. Why is this important?

Hair

Medulla Pattern Description Diagram

Continuous One unbroken line of color

Interrupted(Intermittent)

Pigmented line broken at regular intervals

Fragmented orSegmented

Pigmented line unevenly spaced

Solid Pigmented area filling both the medulla and the cortex

None No separate pigmentation in the medulla