Quiz 1 Flashcards
(187 cards)
1
Q
When the quality of detail in a fingerprint is good, a _________ quantity of features is required to make an identification. When the quality of detail in a fingerprint is low, a _____________ quantity of features is required to make an identification. When the quality is low there will also be a __________ level of tolerance for discrepancies tolerance for discrepancies
A
Smaller
Larger
Higher
2
Q
The primary ridges are located on the underside of the epidermis, located directly below the friction ridges.
T or f
A
True
3
Q
5 layers of the Epidermis
A
Horney
Hyalin
Granular
Spinous
Basel
4
Q
List two specific features that would be considered 2nd level detail.
A
Bifurcations and ridge endings
5
Q
Level 1 detail can be used to exclude a fingermark
A
True
6
Q
List the three layers of skin.
A
Epidermis
Dermis
Hypodermis
7
Q
Who was the first to suggest the centers of disturbance of primate friction ridge formations represent the locations of the volar pads?
A
Wilder
8
Q
Whose study of thin cross sections of fetal skin determined the timing and the development of primary and secondary ridges?
A
Hale
9
Q
Regarding friction skin development, the time of differentiation occurs
between ____ weeks and ____ weeks. During this time _________ ridges begin to appear, and ___________ ridge development ceases in those areas.
A
15-17
secondary
Primary
10
Q
List the three general fingerprint patterns according to SWGFAST.
A
Loop
Whorl
Arch
11
Q
Deposition pressure will always be consistent throughout an impression.
A
False
12
Q
Because incipient ridges are immature ridges, they cannot be used for comparsions
A
False
13
Q
From the list below, select the items that would be considered red flags during fingermark analysis:
A
Extra thick ridges, Misaligned ridges, Angular joints,
Lines running through friction ridge detail.
14
Q
Who described the evolution of the friction ridge skin of mammals, including that all mammals have the same arrangement of volar pads on the hands and feet?
A
Whipple
15
Q
Who studied incipient ridges and determined they are primary ridges that did not fully develop?
A
Okajima
16
Q
The ACE-V process is subjective or objective
A
Subjective
17
Q
Give 2 examples of 3rd level detail:
A
ridge widths, alignment pores
18
Q
Short ridges are often found in the delta
A
True
19
Q
Cells are generated in the ____ layer of the epidermis and sloughed away from
the _____ layer.
A
Basel
Horney
20
Q
On a partially decomposed body in which the epidermis has been sloughed away, the _______ could be used to make a positive identification, as they form rows on either side of the primary ridge in the dermis.
A
dermal papillae
21
Q
The major or primary flexion creases are already established when friction ridges begin to grow
A
True
22
Q
What is the purpose of the analysis phase of ACE-V
A
gathering objective information regarding the fingermark to determine if the impression is suitable for comparison by assessing if there is sufficient quantity and quality of detail
in the impression, while identifying any factors that may distort the appearance of the ridge detail.
23
Q
- With GYRO, features in the fingermark that you are highly confident will be present in the reference print are marked with a xxx dot.
A
Green
24
Q
__________ refers to the anticipated appearance of certain types of minutae in specific parts of a patterns ridge flow due to stresses placed on the developing friction skin in those locations
A
Pattern force
25
The ratio between ridge width and furrow width will indicate the amount of deposition pressure.
True
26
What are the four premises of fingermark identification?
1. Friction ridges develop on the fetus in their definitive form before birth
2. Friction ridges are persistent throughout life except for permanent scarring
3. The specific friction patterns and the details in small areas of friction ridges are unique
and never repeated
4. Overall friction ridge patterns vary within limits which allow for classification
27
A comparison is completed by examining the unknown fingerprint and then the known fingerprint because it allows for an _________ comparison and
discourages __________.
Objective
Bias
28
What two questions must be answered to reach an opinion of identification?
Is there sufficient agreement in the friction ridge detail to identify?
Is there agreement of friction ridge detail between the unknown impression and the known sample?
29
In ACE-V tolerance can be described as a means of expressing the variation that is allowable between two impressions that originated from the same source
True
30
Whose extensive research on friction ridge skin showed volar pad regression occurs almost concurrently with the beginning of primary ridge development?
Cummins
31
Why is friction skin unique
Developmental noise
Random timing (2) – timing of the onset of primary ridge development in
conjunction with regression of the volar pads; timing of onset of secondary ridge
development (time of differentiation)
Random growth (2) – ridge thickness and thinness is random; path a ridge
takes is random, where a ridge starts and stops is random, ridge alignment is
random, pore locations and shapes are random, etc.
Random pressures (2) – pressures from size and shape of volar pads, pressure from
neighboring ridges, pressures in the womb, numerous genetic and physical pressures
32
When considering distortion of a fingermark, a 'C' shape or inverted 'C' shape is indicative of xxx of the digit when the mark was deposited
Twisting
33
Whose extensive research of fetal skin cross-sections showed the development of dermal papillae?
Alfred HALE
34
Who described the evolution of the friction ridge skin of mammals, including that all mammals have the same arrangement of volar pads on the hands and feet?
Inez WHIPPLE
35
Whose extensive research on friction ridge skin showed volar pad regression occurs almost concurrently with the beginning of primary ridge development?
Harold CUMMINGS
36
Whose study of thin cross=-sections of fetal skin determined the timing and the development of primary and secondary ridges?
Alfred HALE
37
Who was the first to suggest these centers of disturbance of primate friction ridge formations .represent the locations of the volar pads?
Harris HAWHORNE WILDER
38
Whose extensive research on friction ridge skin showed the size, location, growth, and configuration of the volar pads affect friction ridge development and the overall fingerprint pattern?
Harold CUMMINGS
39
Who is credited with being the first to recognize that although specific friction ridge arrangements may be similar, they are never duplicated?
JCA MAYOR
40
Who studied incipient ridges and determined they are primary ridges that did not fully develop?
Michio Okajima
41
Who observed that ridge patterns are affected by external forces and by pressure from neighboring ridges?
Inez WHIPPLE
42
What is Ridgeology?
“The study of the uniqueness of the friction skin and its use for personal identification”- David Ashbaugh
43
What are some Structural elements
Desmosomes, basement membrane, dermal papillae and sweat glands
44
2 types of skin:
- smooth skin (hair, sweat glands, sebaceous glands NO FRICTION RIDGES
- Friction skin (volar skin)- May appear lighter, no sebaceous glands, completely covered with ridges (no voids)
45
What are Dermal Papillac?
Are in the Dermis and are “anchors/hooks” that secure the Epidermis. These are located in pockets between ridges in the dermis
46
What are the two important aspects to consider when attempting digit de-termination?
Patterns and Anatomical Considerations
47
In the Canadian fingerprint database, which is the most commonly found pattern?
Ulnar Loop
48
Which hand should be searched first when searching a “clockwise” whorl pattern?
Left
49
What are the indicators that a latent fingerprint was left by a thumb?
Size and shape of impression, a lower pattern area, impression is an edge or side, lone impression, position, tip ridges slope in an ulnar direction, lack of phalange detail
50
Why are finger marks that are adjacent to a latent fingerprint valuable in digit determination?
They can help establish position of digits. Also a small amount of detail in adjacent impressions can help determine overall ridge flow
51
What are some anatomical factors to consider when attempting digit de-termination?
How an item was handled, is it physically possible, the height of the impressions, do you just see edges of impressions, is phalange impression evidence visible
52
Examples of LEVEL 1 details
Pattern type, ridge flow- Can be used to exclude
53
Examples of LEVEL 2 details
Minutia and associated ridge paths and events. Biofications, ridge endings etc
54
Examples of LEVEL 3 details
Ridge width, edge shapes and pores (Adds weight to the identification)
55
4 PREMESIS ********* IMPROTANT FOR EXAM**************
1. Friction ridges develop on the fetus before birth
2. Friction ridges are persistent throughout life except for scaring
3. Specific friction patterns and details in small areas of ridges are unique and never repeated.
4. Patterns vary within limits which allow for classification
56
What is the Philosophy?
Agreement of ridge formations in sequence
57
What does ACE-V stand for?
Analyze
Compare
Evaluate
Verification
58
MOST IMPORTANT FACTORS TO ASSESS DURING ANALYSIS:
1. Reproducibility
2. Specificity
3. Tolerances
59
7 Factors of the analysis phase:
1- Anatomical factors (How it was left and which digit)
2- Substrate
3- Matrix
4- Development Medium (powders chemicals)
5- Deposition Pressure (light, moderate or heavy)
6- Lateral Distortion (movement/smudges)
7- Clarity/Tolerance (higher the clarity, lower the tolerance for differences. Lower the clarity the higher tolerance for differences.
60
Substrate
Matrix
Surface
Whats on finger- Deposited substance (Sweat, sebaceous oils etc)
61
What is TOLERANCE
Higher the clarity, lower the tolerance for differences. Lower the clarity the higher tolerance for differences.
62
What is Tonal Reversal?
Can be caused by excessive pressure. Makes furrows appear black and ridges appear white
63
Two types of compression schemes
* Lossy
* Lossless
64
Pixel properties
Pixels have 3 properties
1. Size
2. Location
3. Color value
65
Low quality
High tolerance
Low quality
High tolerance
66
High quality
Low tolerance
High quality
Low tolerance
67
What is feature weighting?
When evaluating the friction ridge detail, “specificity” “specificity” (rarity) of the
features needs to be taken into consideration
68
The Locard tripartite
rule 1914
If more than 12 concurring minutiae are present 12 concurring minutiae are present and the fingerprint is very clear,
then the certainty of identity is beyond debate debate.
2. If 8 to 12 concurring minutiae are found, then 8 to 12 concurring minutiae are found, then identification is marginal and certainty
of identity is dependent on:
1. the quality (clarity) of the fingerprint,
2. the rarity of the minutiae type,
3. the presence of a core and delta in a clear area
4. the print,
5. the presence of pores, and
6. the perfect agreement of the width of the ridges
7. and furrows, the direction of the ridge flow, and the
8. angular value of the bifurcation bifurcation.
3. If a limited number of characteristic features are present, the fingerprint cannot
provide certainty for an identification , but only a presumption proportional to the
number of points available and their clarity.
69
Is ACE-V subjective or objective?
Subjective
70
Objectivity
is what you can see and explain as a result of your analysis
71
Subjectivity
is a personal decision based on your knowledge, training and
experience.
72
3 possible conclusions of a comparison?
Identification
Exclusion
Inconclusive
73
Identification
Impressions originated from the same source.
74
The two functions of assessing clarity:
Dictates the level of detail (level 1, 2, 3) available for comparison
Dictates the level of Tolerance for differences the level of Tolerance for differences
75
Filters colour pattern that allows its own colour only to pass through. The other colors do not pass
Bayer Pattern
76
Authority to do administration as needed as a peace office
Section 25(1) (b) Criminal Code
77
Types of Powders
- Regular
- Fluorescent
- Magnetic
78
4 purposes of powders
- to make impressions visible
- Contrast
- Easy photography
- Lifting
79
3 types of impressions:
Latent
Visible
Molded
80
Factors to consider for development
* Presence of foreign material
* Type of substrate (non-porous)
* Probable age (age cannot be determined by
appearance)
* Monetary or sentimental value
* Portability
81
Factors to consider for longevity of impressions
* Atmospheric conditions
* Substrate
* Composition of matrix
* Amount of matrix
* Contamination
82
Purpose of powders
* To make the latent impressions visible
* To create contrast with the
background
* To enable the impressions to be
photographed
* To enable the impressions to be lifted
83
Novice error rate
55.18%
84
2 types of Bias
Contextual
- Suspect in custody
- Known suspect
Confirmation
- Know another qualified fingerprint experts analysis
85
Who Studied Bias in forensic science
Itiel E. Dror
86
Why is aperture priority the preferred camera mode for forensic photography?
This mode controls shutter speed.
This mode controls ISO.
This mode controls flash.
This mode better controls depth of field
87
We enhance a digital image of impression evidence, in order to improve
_____________________
Contrast
88
What are the three factors of the exposure triangle?
Shutter Speed
Aperture
ISO
89
In addition to the circle around the impressions, name three things that should be included in the markings of a latent fingerprint, prior to photographing.
R#
Date
Initials
Occ #
90
Latent, visible, and molded are the three types of fingerprints that can be found at a crime scene.
True
91
Research by Tangen et al (Tangen JM, Thompson MB, McCarthy DJ. Identifying Fingerprint Expertise. Psychol. Sci. 2011;22:995-7), clearly demonstrated that expert far outperform novices in fingermark comparisons.
True
92
Selecting the RED channel of an RBG image in Photoshop will darken any red in the digital image.
False
93
The error rate of 4.2% calculated in the Miami-Dade black box study is accurate. (Pacheco, I.; Cerchiai, B.; Stoiloff, S. Miami-Dade Research Study for the Reliability of the ACE-V Process: Accuracy and Precision in Latent Fingerprint Examinations; NCJRS Doc. No. 248534, Dec, 2014.)
False
94
List two enhancement techniques used in Photoshop to enhance a fingerprint. (Use one word or the least number of words possible to describe the technique)
Levels
Greyscale
95
What are the three properties of a pixel?
Colour
Size
Location
96
Applying powder after lifting a fingeprint impression can be an effective method of removing some substrate contamination, removing excess powder, and may provide a better impression than the first lift.
True
97
There are ______ million possible colours with an 8 bit image.
16.7
98
Which researcher is known for studying bias in forensic science?
Itiel Dror
99
The calculated error rate in the FBI/Noblis black box study (Ulery, B. T.; Hicklin, R. A.; Buscaglia, J.; Roberts, M. A. Accuracy and Reliability of Forensic Latent Fingerprint Decisions. PNAS 2011, 108 (19), 7733–7738) is:
.01
100
Changing the aperture from f8 to f11 will double the volume of light.
False
101
Why do we calibrate an image? (choose the correct response)
So we can print the image life-sized
102
Resizing an image changes the number of total pixels in an image.
False
103
Exhibits should be handled in the following manner:
carefully by the edges
104
The process for the recognition of colours in a digital image is colour _______
interpolation.
105
The compression of a JPEG file is considered:
Lossy
106
The best location for the scale on a fingerprint impression is
longitudinal to the fingerprint
107
When using powders, what are your responsibilities to ensure your health and safety as per WHMIS guidelines?
know the materials you are using (SDS)
be aware of the proper safty percautions (know how to protect yoursef)
use the proper personal protective equiptment (PPE).
108
What is the role of channels in Photoshop, as it relates to the forensic photography of fingerprint impressions?
Increase Contrast
109
What bit depth provides a continous tone?
8bit
110
An image taken in RAW format cannot be changed or altered and then saved again in RAW format.
True
111
Why is aperture priority the preferred camera mode for forensic photography?
This mode better controls depth of field
112
We enhance a digital image of impression evidence, in order to improve
Contrast
113
2 types of images
Raster- pixel based
Vector- mathematical formulas logos and icons
114
Three Types of Evidence?
1. Testimonial
Evidence from witnesses, video, audio etc
2. Documentary
Cheques, documents, certificates, photographs etc
3. Physical
Fingerprints, footwear, tire impressions, physical match etc
115
Locard’s Exchange Principle:
When any object or person comes
into contact with an object or
another person, a cross-transfer
of physical evidence occurs
***Every contact leaves a trace***
116
Evidence Four responsibilities from time of collection until court:
1) Identify each piece of evidence
2) Describe exactly where it was found
3) Prove continuity
4) Describe the changes in the evidence
physical damage due to storage
spillage/evaporation
change in physical appearance
117
Things to pay attention to at crime scene such as B&E
Point of entry (POE)
Path leading to point of entry
Point of exit (POX)
Path leading from point of exit
Attempted entry points
Other windows, flowerbeds, etc
Sequence of events within building
118
Good Sources for DNA
Blood
Saliva
Hair Root
Tooth Pulp
Bone Marrow
Skin cells/muscles
Semen
Nasal secretions
119
2 things with LITTLE to NO DNA
Urine and Feces
120
Photo Admissibility in court
Accurate representation of scene
* Proper perspective (free of distortion)
* Relevant
* Unbiased
* Are not there to influence one way or another
* No cropping
* Do not hide anything!!!
121
Linkage
Links your photographs one to the other by using a
common object which is present between one
photograph and the one that follows it.
122
3 ways to increase depth of field
Use a small aperture (ex. f32)
* Increase the camera to subject distance
* Use a shorter focal length (ex. 28 mm)
123
2 Flash Techniques
* Feathered flash
* Bounce flash
124
Techniques for reducing shadows include;
A black background (when appropriate) will help to reduce
shadows. RAISE THE OBJECT OFF THE SURFACE
* Use a light table
* Light diffusion can also reduce the harshness of any shadows
125
What is the depth of field fractions
1/3 in front and 2/3 behind
126
Areas to be swabbed during GSR swabbing?
Hands and Face
127
* Proper exposure and illumination
* Sharp focus (depth of field)
* Fill the frame for maximum resolution
3 important factors in fingerprint photography
128
Fingerprint Photography Closeup. What must be included?
Close-Up (This is the developed fingerprint, scale, circle and
markings. The entire circle and all markings must be included in the
image)
129
Studio Photography
will require the use of
- copy stand
- tripod.
- Continuous lighting
- electronic flash
- Variovs scales
- appropriate back grounds
- light diffusing
130
Daylight balanced light in lumens
5500 kelvins
131
Flash techniques
1. Feathered = hegps reduse an euminate distracting shadows
2. Bounce
132
Camera calibration
- calibrated to record let grey
- White = more light (+ 1)
- Black = take it back (-1)
133
Techniques for reducing shadows
" black background will help reduce the shadows raise object.
off the susface
-> use light table
-> light diffusion can don also reduce the hasshness of any Shadaus
134
Tips for Reducing glare
- light diffusion
- tenting
- proper angle of illumination
- reduce the intensity of the light
135
Grey card
- Use of a grey card can provide proper exposare regardless of the coleur of the object or the beckground
136
What is Macro photography
- Close up
- Usually life size lil - up to 1: 10
- Small objects
- details on a larger object
1. requires the use of macro lens
2. focal length of the lens dictates the working distance (the distance.
between the lens + the object)
137
Painting in light :
@ slow shuter speeds additional light using a
flash light, can be painted in areas of the object
138
Use of reflector
when lighting is uneven consider using
a white material (white card or paper) to reflect light into the darker areas
139
Depth if field macro photography
- depth of field is greatly reduced
- 50% in front 50% m behind object.
- serechng appropriate depth of field is essential
- use depen of field batten reben preview bulton to ensure everything will be in shary focus
140
Tripods
Shutter speed is below
16o th of second
- footwear
- tire impressions
- Blood stains
141
Night phtogrpahy
- Synchronized flash @ the camera
- flash i Slow sync
- flash i rear sync
- multiple flashes at the camer
- multiple flashes away from the camera
142
Night photography Recommendations
- Use shulter release cable to control shulter
- exposure mode set 1o manual
- Shulter speed set to bulb.
- choose appropriate aperture
- manual Focus
143
Flash techniques
- Painting i light
- Anxilirag lighting
- Available light
144
Based on the inverse square law, moving a light source 4 times further away from a subject will reduce the intensity of the light falling on that subject by a factor of:
16
145
Name two types of flash photography that can be used to properly illuminate a scene at night.
Multiple Flashes at camera and Multiple away from camera
146
When painting with light at night, your camera should be in manual mode.
T
147
According to case law, photographic evidence must be fair and must not mislead.
T
148
What are two flash techniques that can be used to photograph a bottle?
Bounce and Feather
149
Based on the hand held rule for the prevention of motion blur, a focal length of 100mm should require a minimum shutter speed of:
1/100
150
Indoor crime scene photographs should always be taken in vertical (portrait) mode.
F
151
After a grey card reading is obtained you must not change the focal length of the lens.
F
152
When swabbing for DNA, what is considered proper PPE to prevent cross-contamination?
Gloves and Mask
153
Linkage is the process of taking a photograph of the scene from each of the four corners of the room.
F
154
When using continuous lighting in studio photography name 2 techniques that can be used to reduce harsh shadows:
Light Table and black backdrop
155
Changing the focal length does not change perspective.
T
156
When taking a grey card reading the camera must be set on Manual shooting mode.
T
157
What is the name of the forensic pioneer responsible for the principle that states: Whenever two objects come in contact, a transfer of material occurs.
Locard
158
When using a grey card to calculate exposure, ensure that your camera mode is on
-- please select --
. Once you obtain a reading you
-- please select --
change the background colour and you
-- please select --
move the camera up or down on the copy stand.
Manual
Can
Can
159
Select 3 ways to increase depth of field.
Close down the aperture
Use a shorter focal length
Increase the camera to subject distance
160
Provide 1 reason for removing the flash from the camera when photographing an exhibit in a crime scene.
Reduce glare
161
Place the following steps in the order you should follow when processing a crime scene .
Speak with the investigator and/or homeowner.
Conduct a walk-through of the scene and determine a safe path.
Determine the path of evidence.
Photograph your crime scene as you found it.
Search for and locate evidence.
Photograph and properly document all evidence.
162
What statement best describes a normal lens?
A lens that has a focal length that depicts the view as seen by the human eye.
163
Of the options below, select the technique that is not a recommended method of reducing glare in studio photography.
Using a black background DOES NOT HELP
164
What are the three types of crime scene photographs?
Overall
Midrange
Closeup
165
Select the responsibilities that we have as Forensic Identification officers regarding evidence, from the time it is collected until it is produced in court.
Describe exactly where the evidence was found.
Prove continuity.
Describe any changes in the evidence
Identify each piece of evidence.
166
What are the three types of evidence?
Testimonial, Documentary and Physical
167
Two recommended types of lighting to be used in studio photography.
Continuous and flash
168
In studio photography what is the main criteria for selecting a background?
Contrast
169
When painting with light at night, your camera should be in manual mode.
T
170
What are two flash techniques that can be used to photograph a bottle?
Feather, bounce
171
Indoor crime scene photographs should always be taken in vertical (portrait) mode.
F
172
When swabbing for DNA, what is considered proper PPE to prevent cross-contamination?
Gloves, Mask
173
Linkage is the process of taking a photograph of the scene from each of the four corners of the room.
F
174
R. v. Mohan, [1994] 2 S.C.R. 9
The test for admissibility of expert testimony:
* Relevance
* Necessity in assisting the trier of fact
Necessity in assisting the trier of fact
* The absence of any exclusionary rule
The absence of any exclusionary rule
* A property qualified expert (reliability of the opinion)
175
R. v. Abbey, 2009 ONCA
Meet the 4 points from Mohan and also allow a gatekeeper phase where the court considers the cost benefit analysis
176
The hallmarks required of every expert witness:
–Impartiality
–Independent
–Unbiased
177
What is expert witness testimony?
Opinion
178
What is a Cartridge?
Projectile (bullet)
Casing
Powder
Primer
179
How do you determine the direction of travel through glass?
Cratering effect
180
2 Types of footwear impressions
Transfer and Takeaway
181
2 types of footwear matrix options
Wet-origin impressions and Dry Origin
182
Difference between oblique and grazed lighting when searching for footwear
Grazed is along the surface. Oblique is up to 90 degrees
183
Dental stone mixture amount
5:2 dental stone to water
184
Palms- 3 Major Creases
Distal Transverse – Proximal Transverse – Thenar (Top, Middle and Bottom)
185
3 palm areas
Interdigital
HypoThenar
Thenar
186
Palm print photography- What photos are required?
The sequence for palm prints is the same as for fingerprints
* Overall
* Midrange
* Close up
* ACAP
187
You may need to take several ACAP photos of different areas
of the palm print. What areas should be photographed individually with scales?
* ACAP of thenar side
* ACAP of hypothenar
* ACAP of interdigital
