Do Now: How observant are you?

1
Do Now How observant are you?

1. On a traffic light where is the green located?
2. On Dice, what number is on the opposite side the
   6?
3. In which hand is the statute of libertys torch?
4. What 2 numbers on a telephone dont have letters
   on them?
5. When you walk how do your arms swing?

2
Do Now How observant are you?

1. On a traffic light where is the green located?
2. On Dice, what number is on the opposite side the
   6?
3. In which hand is the statute of libertys torch?
4. What 2 numbers on a telephone dont have letters
   on them?
5. When you walk how do your arms swing?

Bottom
1, both number always??
Right
1, 0
Opposite
3
Chapter 3 Physical Evidence
4
What is Physical Evidence?

• Any and all objects that can establish that a
  crime has been committed
  OR
• can provide a link between a crime and its
  victim or a crime and its perpetrator.

5
What is Physical Evidence?

• Direct
• Circumstantial
• Physical
• Biological

6
(No Transcript)
7
Evidence

• "Circumstantial evidence can be, and often is
  much more powerful than direct evidence".
• -Robert Precht
• University of Michigan law professor

8
Evidence

• Much of the evidence against convicted American
  bomber Timothy McVeigh was circumstantial, for
  example.
• Ryder rental truck,
• 5,000 pounds (2,300 kg) of ammonium nitrate
  fertilizer, nitromethane, and diesel fuel \
• The 2005 murder trial of Scott Peterson trial was
  another high-profile conviction based heavily on
  circumstantial evidence. Laci and Conner went
  missing between Dec. 23 and Dec. 24, 2002
• Phone calls from Amber Frey
• Hair

9
Do Now How observant are you?

1. Which president is on the one dollar bill?
2. Which way does water go down the drain?
3. Which coins have smooth edges?
4. On a stop sign, what is white?

Washington
Clockwise
Penny, nickle
Stop and border
10
Timothy James McVeigh

• Day 1
• Objective
• What was used as evidence in the case?
• Are their other factors that may have been
  considered?
• Now look at it from the side of the Defense.
• Day 2
• What would be the role of your expert witnesses?
• You will be give 5 minutes to
• Opening argument, expert witness, conclusion

11
Common Types

• Blood, semen, saliva
• Documents
• Drugs
• Explosives
• Fibers
• Fingerprints
• Firearms and ammunition

12
Common Types

• 8. Glass
• 9. Impressions
• 10. hair
• 11. Organs and Physiological fluids
• 12. Paint
• 13. Petroleum products
• 14. Plastic bags
• 15. Plastic, rubber, polymers

13
Common Types

• 16. Powder residues
• 17. Serial numbers
• 18. Soil and minerals
• 19. Tool marks
• 20. Vehicle lights
• 21. Wood and vegetative matter

14
Identification vs. comparison

• And how does it relate to evidence??

15
Identification

• Process of determining a substances physical or
  chemical identity.
• Drug analysis
• Species determination human or not
• Explosive residue analysis

16
Identification

• Steps Involved
• Design systematic analysis that will always test
  for that substance
• Testing must eliminate all other possibilities
• Some substances require 1-10 tests
• FS must be prepared to render a conclusion with
  respect to the origin of the specimen

17
Comparison

• Attempts to ascertain whether two or more objects
  have a common origin.
• Use properties of suspect and control.
• Gives conclusions as probability
• Two types of characteristics

18
ComparisonTwo types of characteristics

• Class characteristics
• Substances can be associated with a group but not
  individual source
• Blood types use factors in blood
• A lot of these can ID suspects at a crime scene
• Individual characteristics
• Substances that are related at almost 100
  probability
• Fingerprints are 1x1060 that 2 peoples are the
  same

19
Do Now What is The Product Rule? (Probability)
20
The Product Rule (Probability)

• Multiplying together the frequencies of
  independently occurring events
• Rolling 2 dices and getting sixes
• 1/6 x1/6 1/36

21
The Product Rule (Probability)
22
O.J.s bloodstain frequencies
Blood Factors Frequency
Type A blood 26
EsD estérase D 85
PGM 22- 2
23
Fiber Evidence and the Wayne Williams Trial

• Items from residence and station wagon.

24
Fiber Evidence and the Wayne Williams Trial

• Tracking Carpet fiber between the two victims
• Assuming
• Carpet installed in one room
• 12x5 room
• Total sales divided between 10 states
• SO 82 rooms with this carpet in Georgia
• Product rule (probability) 1 7,792
• Very low chance

25
Crime scene reconstruction

• The method used to support a likely sequence of
  events by the observations and evaluation of
  physical evidence, as well as statements made by
  witnesses and those involved with the incident.

26
For CSR

• Medical examiner
• Law Enforcement personnel,
• Criminalists

27
Crime scene reconstruction
28

• Finis

29
White Powder Lab
30
1 Living Room Glass table Living Room Glass table Cocaine Cocaine
8 On Kitchen Table Vial A Heroin Heroin
9 On Kitchen Table Vial C Starch heroin, Heroin Starch
10 On Kitchen Table Vial B Starchcrack-cocaine Starch
11 On Kitchen Table Powder over desk Starch Starch
2 Bedroom Vial on burner Cocaine, Crack-cocaine Crack Cocaine
3 Bedroom Test Tube A LSDcocaine Cocaine
4 Bedroom Test Tube B Cocaine Cocaine
5 Bedroom Test Tube C Starchamph Starch
6 Bedroom Test Tube D Starch Starch
7a Closet 1 Opium Opium
7b Closet 2 opium Opium
31
1 Living Room Glass table Living Room Glass table Cocaine, Cocaine
8 On Kitchen Table Vial A Heroin Heroin
9 On Kitchen Table Vial C Crack Cocaine, Starch Heroin Starch
10 On Kitchen Table Vial B Starch
11 On Kitchen Table Powder over desk Starch Starch
2 Bedroom Vial on burner LSD Crack Cocaine
3 Bedroom Test Tube A Cocaine
4 Bedroom Test Tube B LSD Cocaine Cocaine
5 Bedroom Test Tube C Starch Starch
6 Bedroom Test Tube D Opium Starch
7a Closet 1 Meth Opium
7b Closet 2 Opium