Criminalistics: An Introduction to Forensic Science
Class Notes #2
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FACIAL RECONSTRUCTION AND IDENTIFICATION
TRAUMA TYPES AND POSSIBLE CAUSE OF DEATH
GLASS
SOIL
HAIR

FACIAL RECONSTRUCTION AND IDENTIFICATION
    1. Recognize the face
            Burke and Hare- resurrection men
    2. Contours in cardinal directions
            George Buchanan
            Oliver Cromwell
            John Sebastian Bach
            robert the Bruce- King of Scotland
            Karl Pearson- statistician and craniometric
Techniques
    1. Contours in cardinal directions
    2. Fit onto known portraits
    3. 3-D reconstruction onto the cast of the skull
His in 1895
filll in with strips of clay and mold by artist
    4. Photographic superposition
Buck Ruxton Case--Mrs. Ruxton and Mary Rogerson. 1937
    5. X-ray of the skull to provide the 2 dimensional outlines matched to photograph
            Famous- Angel of Death of Auschwitz--Nazi death camp Josef Mengele-Argentina-Uruguay 1985
          Brazil--Clyde Snow
           C.A. Pound Human Identification Laboratory
            Florida Museum of Natural History
University of Florida, Gainesville, FL  William R. Maples
frontal and lateral photos are matched to skull
false positives .6%

TRAUMA TYPES AND POSSIBLE CAUSE OF DEATH
    1.Gunshot wounds
        a. Entrance Small and Circular
        b. Exit is damaging and large- bullet flattened
        c. Entrance wounds small and roundish, radiating cracks
        d. Beveling of the edges on side of direction of travel
        e. Beveling goes in opposite direction on exit wounds
        f. keyhole damage showing direction of bullet from oblique angle

    2. CAT Scan

Trauma
Sharp trauma--Knives and axes
Both cause of death and disposal--dismemberment
Lizzie Borden--Andrew and Abby Borden-father and stepmother
August 1892 Fall Rivers Massachusetts
James E. Starrs Profewssor of Forensic Science at George Washington University


GLASS
Crime scene search, what method?
    There are several small fragments of what appear to be glass--What to do??
        1.--place in what kind of container?
        2. send to crime lab along with transmission forms
        3. what else is obtained?

COMPOSITION: Glass is a hard brittle amorphous material
    1.silicon oxides + metal oxides
    2.sand is melted
    3.soda (Na2CO3) is added to lower melting point
    4. lime is added (CaO) so does not dissolve in water
Common glass metal oxides
    1.sodium, calcium, magnesium and aluminum.
        auto headlight and pyrex - boron oxides
    2.borosilicates

Glass must be identified by its physical properties--chemical signatures and composition are of little value.

PHYSICAL PROPERTIES DESCRIBE A SUBSTANCE WITHOUT REFERENCE
TO ANY OTHER SUBSTANCE - WEIGHT,VOLUME, COLOR, MELTING POINT ETC.
    1.Associate one piece or fragment of glass with another and eliminate or minimize its possible association with all other
    possible pieces of glass.
    2.Must be able to go beyond class characteristics to individual characteristics.

METRIC SYSTEM
grams, kilograms

DENSITY
    Mass = amount of matter
    Weight = m X g
    m = mass
    g = acceleration force of gravity
1.Mass is the same every where
2.Weight varies by the distance from the center of the earth
3.Mass determined by comparison to known standards - balances

VOLUME
1.Metric system can be measured by lengths
    1 liter is defined by the volume of 10 centimeters on a side
    10x10x10=1000cc
    cc=cubic centimeter
    milliliter = ml 1/1000 of a liter
    1,000 cc = 1 liter or 1,000 milliliters
2.Volume IS sensitive to temperature-- expands and contracts

EXAMPLE-
    One gram of water at a room temperature of 20 degrees centigrade has a volume of 1.002 milliliters (ml) and density of 0.998 g/ml

DENSITY OF GLASS
1. FORMULA METHOD
    1.Measure vol. in graduated cylinder
    2.Determine mass on a scale
    3.Obtain density
DENSITY = MASS/VOLUME
2. FLOATATION METHOD
    Mixtures of bromoform and bromobenzene until glass floats.
    Same density to within 0.001 g/ml.

REFRACTIVE INDEX
    1.Light is traveling at about 300,000,000 meters/second in air
    2.glass or water it is slowed down
    3.results in bending prism
    4.prism can separate the light into its component colors
    5.Each color different wave length and different speed

REFRACTIVE INDEX
REFRACTIVE INDEX =VELOCITY OF LIGHT IN VACUUM

VELOCITY OF LIGHT IN MEDIUM

IMMERSION METHOD
MICROSCOPE WITH HOT STAGE
    1.Heat silicone oil at rate of 0.2 degree centigrade
    2.Reveals different refractive indices can see the line where the light bends -

BECKE LINE- See 2. above

FBI have been collecting data
variation in density and variation in refractive index to determine the probability of two pieces of glass being the same by chance alone.
density ranges from 2.47-2.55 and measured to within +/- 0.002
refractive index varies 1.515 - 1.535
can be measured to within +/- 0.001
then 2.55-2.47/0.002 X 1.535 - 1.515/0.001 = 800
800 to one chance.
not independent of each other-- actual odds closer to 100 or 200 to 1
possibility of 2 pieces that fit together not being associated is very remote
physical matching of edges is INDIVIDUALIZED TO ONE SOURCE.
oxidized - proves low beam hot when broken so at night
PHYSICAL MATCHING DEMONSTRATES ABSOLUTE INDIVIDUALIZATION

GLASS FRACTURES
    First bends in the direction of the force
    splintering and cracking and breaking.
    Radial cracks -
    Concentric cracks.
3 Rs - RADIAL - RIGHT ANGLES - REVERSE

PROJECTILES AND BULLETS
    If does not penetrate get the ejection of a small cone of the glass
    Bullets edge will be wedged
    hole wider in the direction of travel
    size of the bullet holes
    laminated glass and plastic sheet
    size of bullet and distances


SOIL
    1. VISUAL APPEARANCE INCLUDING COLOR
    2. PARTICLE SIZE DISTRIBUTION
    3. MINERALOGICAL IDENTIFICATION
    4. INCLUSIONS
    5. PARTICLE-DENSITY DISTRIBUTION
    6. CHEMICAL ANALYSIS
    7. NATURE OF THE CLAYS

COLLECTION OF EVIDENCE
    Sample every 10 to 100 meters
    Check clothing, the shoes, pant cuffs,floor of car, tire treads, and wheel wells
    Place into plastic vials or plastic bags.

1. VISUAL APPEARANCE INCLUDING COLOR
    Munsell Color Book
    oven dry samples
    1100 distinguishable colors.
soil categories:
    along White River - Allegheny, Apison, Cherokee, Leesburg

SOIL
1. VISUAL APPEARANCE INCLUDING COLOR
2. PARTICLE SIZE DISTRIBUTION
3. MINERALOGICAL IDENTIFICATION
4. INCLUSIONS
5. PARTICLE-DENSITY DISTRIBUTION
6. CHEMICAL ANALYSIS
7. NATURE OF THE CLAYS

COLLECTION OF EVIDENCE
    sample every 10 to 100 meters
    clothing, the shoes, pant cuffs,
    floor of car, tire treads, and
    wheel wells
    plastic vials or plastic bags.
1. VISUAL APPEARANCE INCLUDING COLOR
    Munsell Color Book
    oven dry samples
    1100 distinguishable colors.
soil categories:
    along White River - Allegheny Apison, Cherokee, Leesburg

2. PARTICLE SIZE DISTRIBUTION
    sorting screen stack.
    particles between two screens are bigger than the lower one and smaller than the upper one
    standard volume and weight

3. MINERALOGICAL IDENTIFICATION
    1.STANDARD COMPOUND MICROSCOPE
    2.TRANSMITTED WHITE LIGHT
    3.ILLUMINATOR
    4.CONDENSER
    5.SUBSTAGE CONDENSER
    6.STAGE
    7.OBJECTIVE LENSES
    8.EYEPIECE LENSES---virtual image

POLARIZING MICROSCOPE
    1.PRINCIPAL OF POLARIZED LIGHT ---WAVES - LINED UP PASS THROUGH MINERAL AND     CHANGES ANGLE OF DIFFERENT COLORS
    2.CHANGE THE ANGLE OF ANALYZER
    3.MEASURE ANGLE BETWEEN POLARIZER AND ANALYZER
    4.CIRCULAR, GRADUATED CIRCULAR STAGE
    5.EACH MINERAL HAS A STANDARD ANGLE OF EXTINCTION OF STANDARD COLOR
schist into its basic minerals  including free mica.
4.  INCLUSIONS
    foreign particles
 STEREOSCOPIC MICROSCOPE
5. PARTICLE-DENSITY DISTRIBUTION
    density gradient tube technique
    different proportions of tetrabromoethane density 2.96g/ml and ethanol density 0.789g/ml
    layers of 6 to 8 different densities
    Not definitive and must do supplemental tests.

6. CHEMICAL ANALYSIS
   trace elements
7. NATURE OF THE CLAYS
    Dozen clay types: most common groups kaolinite and montmorillonite
    Sheet like crystals and ions of various metals can replace the aluminum
X-ray diffraction widely used straight forward and well-established
    Frye principle.
    atoms organized in planes
   X-rays penetrate the substance
   some bounced off of each plane
   waves are retarded in specific ways
   dark and light bands
   diffraction pattern  "finger print"

HAIR

    Trace evidence section of crime lab
    Chain of evidence submission forms filled out.
    Scrape down room.
    Clothing hung up and brushed

    must also take
CONTROL SAMPLES FROM VICTIM
HEAD HAIR AT LEAST 25
BODY HAIR (BEARD IF MALE)
AXIAL HAIR
PUBIC HAIR

Hair Sampling Method
    when sampling either pull hair or cut off close to skin on both living and dead.
    hairs must be kept separate, handle as little as possible never tape it down to a paper or piece of card board
    clothing or other items need to be packaged separately and sealed with tape and sent to the crime lab

RAPE AND SEXUAL ASSAULT, COMB PUBIC HAIRS OF VICTIM AND SUSPECT BEFORE COLLECTING CONTROL SPECIMENS SO NO CHANCE OF MIXING THE TWO IN THE CONTROLS

WHAT ARE THE GOALS OF HAIR ANALYSIS?
Tie suspect to victim, crime scene, other places and vehicles.

HAIR MORPHOLOGY
Cortex
Cuticle
Medulla
Follicle
Root

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