Fingerprints Flashcards
According to the King Country video, when will we know if someone is in AFIS
within 30 mins
According to the King Country video, fingerprints are found in how many crime scenes
67%
According to the King Country video, how many of found prints are identified
37%
According to the King Country video, how many of found prints are a different conclusion than identification
63%
what is the canadian equivilant for NIJ
there is none
what are the commonly used fingerprint classes
- whorl
- right loop
- arch
- tented arch
- left loop
- double loop
what three primary glands contribute to the production of sweat
- eccrine
- appocrine
- sebacious
what are the chemical compounds found in eccrine glands
- urea
- lactate
- note that they’re small molecules
- there are lots of others, but these two are the main ones
what are the chemical compounds found in apocrine glands
- proteins (polymer of AA)
- sugars (carbs of 5-6 rings)
- note that they’re larger molecules
what are the chemical compounds found in sebacious glands
- fatty acids
- triglycerides
- note they’re both small molecules
true/false Each gland contributes a unique mixture of chemical compounds
true
what are the two possible ways for the chem compounds that form fingerprints to get to the friction ridge
- either exude from the pores onto the ridges
- transfered onto the ridges through touching an area
true/false it is a fair assumption that a latent print is a mix of all the secretions from all 3 types of glands
- FALSE
- is either a mix of some or all
- depends on the eprson
what are the classes of surfaces
- porous
- nonporous
true/false nonporous surface absorb
- FALSE
- they repel moisture, and often appear polished
what are some nonporous surfaces
- glass
- plastic
- metal
- ceramic
- laminete floor (fake wood)
latent prints on what type of surface are more susceptible to damage and why
- nonporous
- cause the fingerprint residue is on the outermost surface
what should be used for fingerprints on nonporous surfaces
cyanoacrylate (CA) superglue
how do we use the fuming of cyanoacrylate to develop fingerprints
- exposure of a latent fingerprint to ethyl-cyanoacrylate vapor in an enclosed chamber
- note that it MUST be ethyl-CA, not just CA
- when the fingerprint comes in contact w the cyanoacrylate monomer in the vapour, white polymer grows along the ridges of the print
what are the issues of using the fuming of cyanoacrylate to develop fingerprints
- if the substrate the print is on is white or transparent, we wont be able to see
- we need a chamber, harsh chemicals, and lab
- cannot be done onsite
- destructive to evidence
what are some porous surfaces
- paper
- wood
- cardboard
what are the best techniques for porous surfaces
- amino acid techniques
- cause AAs tend to remain stationary when absorbed, and won’t migrate
latent fingerprints on porous surfaces should be developed how
- w ninhydrin
- reacts w AA (proteins)
what surfaces can 1,2-Idanedione be used on
- porous
- nonporous
what is a safer, cheaper alternative used to develop fingerprints
1,2-Idanedione
how does 1,2-Idanedione work
makes fingerprints glow when hit by certain wavelengths of light
true/false 1,2-Idanedione can be used on site
true
true/false 1,2-Idanedione needs a chamber/ lab
false
how can we improve the development of latent fingerprints
- offer increased sensitivity and signal-to-noise ratio;
- avoid background colour interference
- be readily deployed at crime scenes;
- be introduced in sequences of detection techniques or in sequences with other forensic investigation methods (e.g., DNA profiling);
- simplify the detection process by reducing the number of steps or allowing automation;
- reduce the overall cost of fingerprint processing;
- avoid the use of hazardous chemicals
what does it mean if a fingerprint scored 0 on the Bandey scale
- absence of any detail
- no development
what does it mean if a fingerprint scored 1 on the Bandey scale
- level 1 ridge characteristics
- no continuous ridges: all discontinuous or dotty
what does it mean if a fingerprint scored 2 on the Bandey scale
- level 2 ridge details present
- 1/3 of the mark comprised of continuous ridges
- remainder is no development or dotty
what does it mean if a fingerprint scored 3 on the Bandey scale
- level 3 ridge details present
- 2/3 of the mark comprised of continuous ridges
- remaining is no development or dotty
what does it mean if a fingerprint scored 4 on the Bandey scale
- full development
- whole mark comprised of continuous ridges
- very rarely seen
what is the scientific process to evaluate fingerprints
ACE-V
what does ACE-V stand for
- analysis
- comparison
- evaluation
- verification
who came up with ACE-V and when
- David Ashbaugh
- 1980s
- a canadian fingerprint expert
what is involved in the analysis part of ACE-V
examiner assesses the unknown print to determine whether or not it is suitable for comparison
what is involved in the comparison part of ACE-V
examiner analyzes the characteristic attributed to the FP and identifies conformities between the found and the unknown latent print
what is involved in the evaluation part of ACE-V
- examiner asks a few questions
- are there any conformities between the revealed print and the known ones?
- is there a sufficient number of minutiae to identify the unique correlation?
what is involved in the evaluation part of ACE-V
come to a conclusion
what are the possible conclusions for fingerprints
- identified
- not identified/ excluded
- inconclusive
- verified
what is involved in the verification part of ACE-V
another FP examiner must make a conclusion
Most law enforcement AFIS installations have the ability to perform what functions
- search a set of known fingerprints against existing database with better than 99% accuracy
- search latent prints against an existing database
- search latent from a CS to latent from a diff CS
- new tenprint to pre-existing unsolved latent
what are tenprints
known fingerprints
what have been developed to allow other functions that expand AFIS capabilities
enhancements
what are some enhancements that have been developed to allow other functions that expand AFIS capabilities
- addition of palmprint records
- interfacing of AFIS w other crim justice info systems
- addition of hand-held portable devices for use in the field
- multimodal identification systems
what other crim justice info systems is AFIS being interfaced with
- digital mug shot systems
- livescan fingerprint capture devices
what different things are multimodal identification systems being used to identify
- fingerprint
- palmprint
- iris
- facial recognition
why might Developing and recovering debris-covered fingerprints be challenging
- the layer of debris needs to be removed before the fingerprint development
- but the removal of debris could damage the fingerprints underneath.
what is a new way to pre-treat debris covered latent fingerprints from the exterior of surfaces
use of liquid latex
in the study where they looked into using liquid latex for debris covered fingerprints, what was the sample size
- 540 latent prints from 1 donor
- fingerprints put on 3 diff vehicles
in the study where they looked into using liquid latex for debris covered fingerprints, how were the fingerprints developed
- 1/2 using traditional black powder
- 1/2 using liquid latex pre-treatment, followed by traditional black powder
in the study where they looked into using liquid latex for debris covered fingerprints, what was the fingerprint recovery rate
- 149/540
- 27%
in the study where they looked into using liquid latex for debris covered fingerprints, how many of the FP using liquid latex pre-treatment contained level 1 detail
83%
what are close non-matches (CNMs)
when two prints from different sources have many common features and few dissimilar features
why are close non-matches (CNMs) increasing
as more fingerprints in the databases, the more CNMs
how many fingerprint agencies completed a mandatory proficiency test for CNMs
125
what was the false-pos error rate for the fingerprint agencies that completed a mandatory proficiency test for CNMs
20%
describe the madrid case
- march 11 2004
- terrorists detonated bombs on several commuter trains in Madrid
how many people were killed in the madrid case
200
how many people were injured in the madrid case
1400
what was the error in the madrid case
- fingerprints recovered on a bag of detonators connected w attacks
- fingerprints transmitted to INTERPOL w request that FBI help
- march 19 2004 FBI identified Brandon Mayfield as one of the sources
- AFIS generated a list of 20 candidate prints as a potential match for latent fingerprint 17
- FBI examiner 1 used side by side comparison and identified LFP 17 to be Brandon’s
- FBI examiner 2 verified this
- April 13 2004 FBI learned Spain police has examined it and yielded a neg result
- may 19 2004 spain police identifed LFP 17 as a fingerprint of someone else
what factors cause the misidentification of prints in the madrid case
- unusual similarity between prints
- errors in the exam procedure
- examiners relied on level 3 (tiny) details
- examiners ignored other level 3 details that were not in agreement
- inadequate explanations for difference in appearance
- pressure of working on a high-profile terrorism case
- contextual bias
what was made to standardize language used by Department of Justice fingerprint examiners in their reports and testimony
Uniform Language for Testimony and Reporting (ULTR) document for fingerprints done in 2018
what statements were examiners prohibited from saying
a) “two friction ridge prints originated from the same source to the absolute exclusion of all other sources;”
b) using terms like “individualize” or “reasonable degree of scientific certainty;”
c) expressing 100% certainty; or
d) implying that fingerprint examination has a zero error rate
true/false there is a QA/QC method to determine the efficacy of fingerprint developing reagents
false
why is aging of fingerprints a major challenge
- because of progressive degradation of the organic compounds under the influence of various atmospheric parameters
- Once a fingerprint is deposited, its composition becomes subject to change and smudging
true/false a method exists to reliably predict the age of a latent fingerprint
false
true/false the type of surface impacts the quality of the image
true
image on plain glass is of ______ (higher/lower) quality than the image on stainless steel
higher
what is fingerprint smudging
diffusion of endogenous fingerprint compounds
what are endogenous fingerprint compounds
- fatty acids
- triacylglycerides
what might be a way to determine the age of fingerprints
the diffusion of fatty acids ad triacylglycerides on the surface
true/false there was fingerprint evidence in the R v Mercer case
true (palmprint)
where were the palmprints found in the R v Mercer case
- on the windowsill
- perpendicular to the sill
what can be assume based on the placement of the palmprint in the R v Mercer case
- placed his hands on the sill from outside the house
- then pulled himself up to the window
- but the window is high, so its unlikely he could have done this without help
what was the accused charged with in R v Bornyk
- break and enter
- theft
what did the crowns case rely on in R v Bornyk
a single fingerprint found inside the home
describe the fingerprint in R v Bornyk
- partial, latent
- found on the plastic wrapping of a box containing a carnival ghoulish doll
- large portion of the print was distorted by rippled in the plastic wrap
- the distorted part includes where ridge formations like loops and whorls are normally found
true/false the investigator in R v Bornyk was qualified
- TRUE
- no objections to his ability
what did Corporal Wolbeck use to locate the fingerprint in R v Bornyk
black powder
what does AFIS stand for
automated fingerprint identification system
in R v Bornyk, did they get any matches with the fingerprint
- not initially (in 2010)
- negative
- it would stay in the system and search daily for all new incoming 10-point entries
- they then found a possible match in 2011 from a form back in 2006
- Corporal Wolbeck did an expert analysis
is it weird that the set of 2006 fingerprints and 2010 fingerprints didn’t match before 2011
yes
what was the explanation for why the 2006 fingerprints and 2010 fingerprints didn’t match before 2011
no clear explanation happened at trial
what report did Corporal Wolbeck do in R v Bornyk and what did it say
- Friction Ridge Analysis
- states he used the ACE-V method
