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1
Chapter 4
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(No Transcript)
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Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
4
Collecting,
5
Collecting,
Identifying and Managing
Q 21
6
Collecting,
Identifying and Managing
Physical Evidence
Q 1, 10, 27
7
The Crime Lab
A group of laboratories under one roof..
8
The Crime Lab
Each lab specializes in its own branch of science
9
The Crime Lab
Pathology Odontology Toxicology Ballistics
10
Crime Labs
Work closely with investigators and police
personnel in determining who may or may not have
committed a crime
11
DNA Profiling
An advanced area in crime lab technology- called
DNA typing or DNA profiling
12
What is DNA ?
D
N
A
13
What is DNA ?
D
eoxyribo-
N
A
14
What is DNA ?
D
eoxyribo-
N
ucleic
A
15
What is DNA ?
D
eoxyribo-
N
ucleic
A
cid
16
What is DNA ?
A molecule present in all forms of life
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What is DNA ?
The substance which determines traits and genetic
disposition
Q 22, 23
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Submitting Evidence

• When submitting evidence to the lab, include

• Date
• Case number
• Nature of crime

19
Submitting Evidence

• When submitting evidence to the lab, include

• Location of crime
• Involved parties
• Crime scene report

20
(No Transcript)
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Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
22
Blood As Evidence
Most common form of evidence found at the scene
of serious and violent crimes
23
Blood As Evidence
Most common form of evidence found at the scene
of serious and violent crimes
24
Blood As Evidence
Most common form of evidence found at the scene
of serious and violent crimes
25
Blood As Evidence
Most common form of evidence found at the scene
of serious and violent crimes
26
Blood As Evidence
Most common form of evidence found at the scene
of serious and violent crimes
27
Blood As Evidence
Most common form of evidence found at the scene
of serious and violent crimes
28
Blood As Evidence
Most common form of evidence found at the scene
of serious and violent crimes
29
Blood As Evidence
Splatters Droplets Puddles Smears Trace amounts
Blood evidence may be found in...
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Blood As Evidence
Dried spills or drops of blood
Bloodstains are
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Blood As Evidence
Reagents are
Substances used to detect or test for blood or
other substances
32
Blood As Evidence
Blood drops, blood splashes or splatters reveal
much about a crime
Q 29
33
Blood As Evidence
Velocity
Blood drops or spots can tell
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Blood As Evidence
Impact Angle
Blood drops or spots can tell
35
Blood As Evidence
Distance
Blood drops or spots can tell
36
Blood As Evidence
The direction of the falling drops that produced
them
Blood Splatters Reveal
Q 3
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Blood As Evidence
Blood typing 4 major groups

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Blood As Evidence
Blood typing 4 major groups
A

39
Blood As Evidence
Blood typing 4 major groups
A

B
40
Blood As Evidence
Blood typing 4 major groups
A

B
AB
41
Blood As Evidence
Blood typing 4 major groups
A

B
AB
O
42
Blood As Evidence
Blood typing
Rh factor
Can be positive or negative
Q 2, 24
43
Blood As Evidence
Results of Lab Exam
Is it blood? Is it human? If human, what blood
type?
Q 11
44
Bloodstains are valuable evidence in

• Rape
• Assault and Murder
• Burglary, Hit and Run

Q 12
45
(No Transcript)
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Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
47
Semen as Evidence
Must be handled carefully- not break up
spermatazoa
DNA in semen sample
48
Semen as Evidence
Results from Lab Exam
Does the sample contain human semen?
49
Semen as Evidence
Results from Lab Exam
Can the blood group of the semen be determined?
50
Semen as Evidence
Results from Lab Exam
If blood specimen from suspect is available, does
it match DNA in the sample?
51
Semen is valuable evidence in
Death Rape Sexual Assaults other than Rape
Q 4, 30
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(No Transcript)
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Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
54
Hair as Evidence
Valuable means of identification

• Retains structural features for long periods

Q 13
55
Hair as Evidence
Valuable means of identification

• Can be used to identify a persons race or gender

56
Hair as Evidence
Results from Lab Exam
Is hair sample human or animal? If human, what
part of body?
57
Hair as Evidence
Results from Lab Exam
If animal, what species? Any characteristics of
the person?
58
Hair as Evidence
Results from Lab Exam
Did hair fall out naturally, or was it pulled
out?
59
Hair as Evidence
Results from Lab Exam
Are there any foreign substances in the hair?
60
Hair is valuable evidence in
Assault cases Rape and Sexual assaults Hit and
Run Death
Q 9
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(No Transcript)
62
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Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
63
Fibers as Evidence

• Fibers occur at scene of a crime more frequently
  than any other type of microscopic evidence

Q 25
64
Fibers as Evidence

• Fiber Collection

Adhesive Tape Method
Tape is used to cover an area and pick up fibers
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Fibers as Evidence

• Fiber Collection

Adhesive Tape Method
Fibers adhere to sticky surface of the tape
66
Fibers as Evidence
Mineral Animal Vegetable Synthetic

• Four groups of fibers

Q 14
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Fibers as Evidence
Vegetable Fibers

• Cotton
• Jute
• Hemp
• Linen

68
Fibers as Evidence
Mineral Fibers

• Glass
• Asbestos

69
Fibers as Evidence

• Wool
• Silk
• Cashmere
• Fur

AnimalFibers
70
Fibers as Evidence
Synthetic Fibers

• Nylon
• Rayon
• Polyester

71
Fibers as Evidence
Results from Lab Exam

• Type of Fiber
• Match or no match to victim or suspect

72
Fibers as Evidence
Results from Lab Exam

• Any similarities noted?

73
Fibers are valuable evidence in
Assault Burglary Death Rape and Sexual assaults
Q 8
74
(No Transcript)
75
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Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
76
Glass as Evidence

• Glass

Produced in many ways Variety of formulas
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Glass as Evidence

• Glass

Variations of light and refraction make it a
valuable form of evidence
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Glass as Evidence

• Glass

Very tiny shards of glass adhere to suspects
shoes, clothes or hair
Q 26
79
Glass as Evidence

• Radial Fractures

Cracks at center of area
80
Glass as Evidence

• Radial Fractures

Cracks at center of area
Radiate outward
81
Glass as Evidence

• Radial Fractures

Cracks at center of area
Form starburst pattern
Radiate outward
82
Glass as Evidence

• Concentric Fractures

Circular crack patterns in the glass around the
point of impact
83
Glass as Evidence

• Concentric Fractures

Circular crack patterns in the glass around the
point of impact
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Glass as Evidence

• Concentric Fractures

Circular crack patterns in the glass around the
point of impact
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Glass as Evidence

• Concentric Fractures

Circular crack patterns in the glass around the
point of impact
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Glass as Evidence

• Concentric Fractures

Circular crack patterns in the glass around the
point of impact
Graphic
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(No Transcript)
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
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Glass as Evidence

• Conchoidal Fractures

Curved lines along the edge of broken glass
Q 15
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Glass as Evidence

• Conchoidal Fractures

Forms a shell or cone-shaped pattern
Graphic
Q 7
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(No Transcript)
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Glass as Evidence

• Results from Lab Exam

If a window is struck by blunt instrument, from
which side struck?
99
Glass as Evidence

• Results from Lab Exam

If struck by a bullet, which side fired from?
100
Glass as Evidence

• Results from Lab Exam

If 2 or more bullets fired, what is the firing
sequence?
101
Glass is valuable evidence in
Burglary Hit and Run
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(No Transcript)
103
Menu
Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
104
Lets Discuss
105
Breaking and Entering
Alarm is triggered at the ACME Balloon company
106
Breaking and Entering
Alarm is triggered at the ACME Balloon
company New formula non- deflatable balloon
107
Breaking and Entering
Alarm is triggered at the ACME Balloon
company New formula non- deflatable balloon
108
Breaking and Entering
Alarm is triggered at the ACME Balloon
company New formula non- deflatable balloon
109
The Formula
Worth a fortune in the industry Military
potential for spy balloons
110
The break in appears to have been through a glass
window on the north end of the factory.
ACME
111
The break in appears to have been through a glass
window on the north end of the factory.
ACME
112
The break in appears to have been through a glass
window on the north end of the factory.
ACME
113
The break in appears to have been through a glass
window on the north end of the factory.
ACME
114
The break in appears to have been through a glass
window on the north end of the factory.
ACME
115
As one of the responding investigators what would
you look for at the window? Would you look
anywhere else for evidence?
116
If the door had a metal handle, what evidence
might it provide? Would you look for clothing
fibers at this scene? Where would you look?
117
(No Transcript)
118
Menu
Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
119
Paint as Evidence

• Occurs as physical evidence in three forms

Chips or Flakes Smears Intact Finishes
Q 5, 16
120
Paint as Evidence

• Paint Chips or Flakes

Small particles of dried paint - may adhere to
clothing, or may be found at scene of accidents
Q 28
121
Paint as Evidence

• Paint Smears
• Smears of paint from either fresh paint or old
  chalking paint.

122
Paint as Evidence

• Intact Paint Finishes
• Painted finishes on tools or automobiles at the
  scene of the crime

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Paint as Evidence

• Intact Paint Finishes
• Painted finishes on tools or automobiles at the
  scene of the crime

124
Paint as Evidence

• Intact Paint Finishes
• Painted finishes on tools or automobiles at the
  scene of the crime

125
Paint as Evidence

• Intact Paint Finishes
• Painted finishes on tools or automobiles at the
  scene of the crime

126
Paint as Evidence
Results from Lab exam
Can flakes of paint provide conclusive
identification of the paints source?
127
Paint as Evidence
Results from Lab exam
Can a paint chip establish conclusive
identification of an automobile?
128
Paint is valuable evidence in
Burglary Hit and Run
Q 6
129
(No Transcript)
130
Menu
Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
131
Firearms and Ammunition as Evidence
132
Firearms and Ammunition as Evidence
Common at Many Crime Scenes
Revolvers Loaded cartridges Pistols
133
Firearms and Ammunition as Evidence
Common at Many Crime Scenes
Powder Residues Casings Shot Pellets
134
Firearms and Ammunition as Evidence
Investigators should know the difference between
A pistol and a revolver
135
Firearms and Ammunition as Evidence
Investigators should know the difference between
A rifle and a shotgun
136
Firearms and Ammunition as Evidence
The Bore
137
Firearms and Ammunition as Evidence
The Bore
Q 17
138
Firearms and Ammunition as Evidence
The Bore
The hollow or cylindrical chamber or barrel of a
firearm
139
Firearms and Ammunition as Evidence
Striations
Marks, lines or scratches on the hard surface of
the bullet
140
Firearms and Ammunition as Evidence
Striations
Marks, lines or scratches on the hard surface of
the bullet
Q 18
141
Firearms and Ammunition as Evidence
Results from Lab Exam
Type or make of firearm that fired the bullet
142
Firearms and Ammunition as Evidence
Results from Lab Exam
Was a bullet fired from a particular gun?
143
Firearms and Ammunition as Evidence
Results from Lab Exam
Were multiple bullets fired from the same gun?
144
Firearms and Ammunition as Evidence
Results from Lab Exam
Was a cartridge fired from a particular gun?
145
Firearms and Ammunition as Evidence
Results from Lab Exam
What was the gauge of the shotgun?
146
Firearms and Ammunition as Evidence
Results from Lab Exam
What size shot was used?
147
Firearms and Ammunition as Evidence
Results from Lab Exam
How far from the victim was the gun held?
148
Firearms and Ammunition as Evidence
Results from Lab Exam
What was the serial number of the gun?
149
Firearms and Ammunition as Evidence
Results from Lab Exam
Was the gun carried in the suspects pocket?
150
Firearms and Ammunition as Evidence
Results from Lab Exam
Any foreign material attached to the bullet?
(Indicates path of flight)
151
Firearms and Ammunition as Evidence
Results from Lab Exam
Gun ever been used in a previous offense?
152
Firearms and Ammunition as Evidence
Results from Lab Exam
Any fingerprints on the weapon, shells or
cartridges?
153
Firearms and Ammunition are valuable evidence in
Aggravated assault Homicides Drug Cases
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(No Transcript)
155
Menu
Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
156
Drugs as Evidence
Criminals are often high on drugs or alcohol- May
conceal drugs anywhere
157
Drugs as Evidence
Criminals are often high on drugs or alcohol- May
conceal drugs anywhere
158
Drugs as Evidence
Criminals are often high on drugs or alcohol- May
conceal drugs anywhere
159
Drugs as Evidence
Results of Lab Exam
Confirmation of corpus dilecti by identifying
unknown substance found at the scene
Graphic
Q 19
160
(No Transcript)
161
Drugs as Evidence
Results of Lab Exam
Identification of designer drugs
162
Drugs as Evidence
Results of Lab Exam
Quantification of amount of an illegal drug
163
Drugs are valuable evidence in
Assault Death Illegal drug laboratories
164
(No Transcript)
165
Menu
Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
166
Documents as Evidence
A document is anything on which a mark has been
made to convey a message
167
Documents as Evidence
Compare specimens with known standards
168
Documents as Evidence
Comparison specimens of documents require
Several samples of writing from the suspect
169
Documents as Evidence
Comparison specimens of documents require
Writing samples should be from information
dictated by the investigator
170
Documents as Evidence
Comparison specimens of documents require
Obtain written samples of the suspect from other
sources
171
Documents as Evidence
Comparison specimens of documents require
Use similar materials to that of original document
172
Documents as Evidence
Comparison specimens of documents require
10 - 15 samples of signature in question
173
Documents as Evidence
Typewriter Comparisons
Type specimen on paper similar to that of
questioned document
174
Documents as Evidence
Typewriter Comparisons
Type questioned text word-for-word at least three
times
175
Documents as Evidence
Typewriter Comparisons
On separate sheet of paper, type several letter
groupings
176
Documents as Evidence
Typewriter Comparisons
Type 3 complete impressions of the typewriter
typeface made by striking all keys in a row
177
Documents as Evidence
Typewriter Comparisons
Remove the ribbon, submit to lab along with
typing specimens
178
Documents as Evidence
Computer Printer Comparisons
Dot matrix printers, laser printers and ink jet
printers create uniquely identifiable characters
179
Documents as Evidence
Computer Printer Comparisons
Dot matrix printers, laser printers and ink jet
printers create uniquely identifiable characters
180
Documents as Evidence
Computer Printer Comparisons
Dot matrix printers, laser printers and ink jet
printers create uniquely identifiable characters
181
Documents as Evidence
Computer Printer Comparisons
Use procedures for typewriter specimens for
computer printers
182
Documents as Evidence
Results from Laboratory Exam
Was a document written by a particular
individual? Is a particular writing forged?
183
Documents as Evidence
Results from Laboratory Exam
What was the age/ make/ model of the typewriter /
printer? Was a particular printer or typewriter
used to write the document?
184
Documents as Evidence
Results from Laboratory Exam
What differences are there between inks? Did two
pieces of paper come from the same source?
185
Documents as Evidence
Results from Laboratory Exam
Do uneven edges on torn paper match? Will creases
or folds of a document reveal its origin or path
of travel?
186
Documents as Evidence
Results from Laboratory Exam
What is the content of writing on burned or
charred paper?
187
Documents are valuable evidence in
Suicide Kidnapping Forgeries Extortion
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(No Transcript)
189
Menu
Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
190
Flammables as Evidence
To preserve as evidence
Prevent volatile liquids from evaporating
191
Flammables as Evidence
To preserve as evidence
Samples should be sealed in original container
192
Flammables as Evidence
Results from Lab Exam
Confirmation of corpus delicti - isolating
flammable liquid and Identifying it.
193
Flammables as Evidence
Results from Lab Exam
Connection of flammables to suspect
194
Flammables as Evidence
Results from Lab Exam
Connection of flammables to suspect
195
Flammables as Evidence
Results from Lab Exam
Connection of flammables to suspect
196
Flammables are valuable evidence in
Arsons Theft (of the flammables)
197
Corrosive Materials as Evidence
Acids and Alkalies require special handling!
198
Corrosive Materials as Evidence
Consult a laboratory expert before handling,
preparing or transporting any such liquid
Q 20
199
Explosives as Evidence
Whenever dangerous explosives are found, clear
the area
200
Explosives as Evidence
Call the crime lab and the bomb disposal unit
201
Explosives as Evidence
Call the crime lab and the bomb disposal unit
202
(No Transcript)
203
Menu
Crime Lab and DNA Profiling
Blood
Paint
Semen
Firearms
Hair
Drugs
Fiber
Documents
Glass
Flammables
Scenario Break and Enter
Scenarios The Huge Estate Case /Incredulous
Credentials
204
Lets Discuss
205
The Huge Case
Estate of Howard Huge Reclusive entrepreneur
found dead
206
Suspicious Conditions
One estranged wife, two ex-wives, many children,
legitimate and otherwise
207
Suspicious Conditions
One estranged wife, two ex-wives, many children,
legitimate and otherwise
208
Suspicious Conditions
One estranged wife, two ex-wives, many children,
legitimate and otherwise
209
Suspicious Conditions
One estranged wife, two ex-wives, many children,
legitimate and otherwise
210
Suspicious...
211
Suspicious...
212
Suspicious...
At the crime scene, a hand- written will is found
on a torn scrap of paper It leaves the estate to
his children
213
Suspicious...
At the crime scene, a hand- written will is found
on a torn scrap of paper It appears to be
important evidence
214
As the lead investigator on the scene answer the
following
Whose handwriting samples will you request? What
document will you use for comparison to the
samples?
215
As the lead investigator on the scene answer the
following
How will you protect the document you have
obtained? What lab tests will you request?
216
(No Transcript)
217
Incredulous Credentials

• Professor Arnold Nelson applied to Metro
  University with an impressive set of
  credentials

218
Incredulous Credentials

• Letters from government officials
• Awards from famous organizations

219
Incredulous Credentials

• and a Ph.D. from Prestigious University
• Everything was signed and notarized, but...

220
Incredulous Credentials

• Administrators at Metro U. were skeptical of
  Nelsons degree

221
Incredulous Credentials

• Four Metro professors had been awarded honorary
  degrees from Prestigious U. which look
  completely different

222
Incredulous Credentials

• Officials at Prestigious U. were unable to refute
  Nelsons claim of a degree from their college

223
Incredulous Credentials

• All records were lost when the
  admin building burned to the ground
  during the student riots of the late 1960s

224
Incredulous Credentials

• All records were lost when the
  admin building burned to the ground
  during the student riots of the late 1960s

225
Incredulous Credentials

• You are a member of the campus police, assigned
  to investigate Professor Nelsons academic
  credentials

226
Incredulous Credentials

• How many comparison documents will you need to
  submit for analysis?

227
Incredulous Credentials

• Name at least three tests you want the lab to run

228
Incredulous Credentials

• What results might the lab report provide?

229
(No Transcript)