Fingerprints dactylograms
CHS
Forensics
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Topics
– History
– Fundamental Principles
– Automated fingerprint Identification System (AFIS)
– Methods of detection
– Preservation
– Digital imaging
History of fingerprinting
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Evidence exists that the ______________ used fingerprints to sign documents as
far back as three thousand years ago.
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Henry ______________ suggested that skin ridge patterns could be important in
identifying criminals
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______________ described an incident about a thief who left his fingerprints on a
______________ washed wall.
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He compared this print with some suspects, he found they were all very
______________.
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A few days later another suspect whose ______________ matched the ones on the
wall, when confronted with the evidence, he ______________.
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Francis ______________ did extensive research into fingerprinting.
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His book “______________ ______________” was the impetus for police agencies
accepting their importance in ______________ investigations.
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When the police took the Bertolion measurements for Will West, they matched
exactly those taken previously from a ______________ prisoner William West.
Police seemed to know the reason for this: Will West was lying. He was the earlier
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William West, who had ______________ his name in order to save himself for the
harsh punishments meted out to recidivists.
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No amount of pleadings would have had any effect on the police, had they not
discovered that William West was already in ______________ at that time!
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The two were ______________ together, everyone was amazed. They looked exactly
alike. Here was the strangest case in the history of identification - two people
apparently unrelated (they denied being related, although it has been established now
that they were identical twins), having exactly the same ______________ and the
same Bertillon ______________. How could one be differentiated from the other?
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Fundamental Principles
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______________ Principle- A fingerprint is an ______________ characteristic
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______________ Principle- Fingerprints will remain ______________ for a
______________
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______________ Principle- Fingerprints have ______________ characteristics
that allow them to be ______________.
 ______________ principle
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A fingerprint is an ______________ characteristic, & therefore no two are
______________
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Galton calculated that there are ______________ different possible fingerprints.
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This is ______________ by both research and that over the past 90 years no two
fingerprints have been ______________.
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The individuality of a finger print is not determined by its general shape or pattern
but by a careful study of its ______________ characteristics A.K.A.
______________
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Ridge charecteristics
Ridge ending
Double bifurcation
Bifurcation
Trifurcation
Dot
Opposed bifurcations
Island (short ridge)
Ridge crossing
Lake (enclosure)
Opposed bifurcation/ridge
Hook (spur)
ending
Bridge
 ______________ principle
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A fingerprint will remain ______________ for the ______________ of an
individual.
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A visual inspection of a finger shows a series of lines ______________
(______________) and ______________ (______________).
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______________ carry sweat to the surface of the skin
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Once the finger touches a surface the ______________ and ______________ on
the finger are transferred to the surface.
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They are ______________ to the naked eye and are called ______________
Fingerprints.
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The only way to alter fingerprints is by ______________ ______________.
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John ______________, a ______________ and vicious thief. Terrorized the
Midwest during the great ______________.
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He and his gang killed 10 men & wound wounding 7 others, robbing banks and police
arsenals, and staging 3 jail breaks killing a ______________ during one and wounding
2 ______________ in another.
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He tried to permanently alter his ______________ with the use of
______________.
 ______________ Principle
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Fingerprints have general ridge ______________ that permit them to be
systematically ______________.
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All fingerprints are divided into three main ______________
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______________
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______________
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______________
______________ - ______ % of the worlds population displays
this type of pattern
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Draw and describe the pattern _________________________
___________________________________________________
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If the ______________ opens toward the little finger it is called an
______________ Loop
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If the ______________ opens toward the thumb it is called a ______________
Loop
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______________ is the ridge nearest the type line divergence
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______________
_____- _____% of the worlds population displays this type of
pattern.
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Draw and describe the pattern _________________________
___________________________________________________
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4 types; ______________ whorl, ______________ whorl,
______________ pocket loop whorl, ______________ whorl
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______________ ___% of the worlds population displays this type of pattern.
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Draw and describe the pattern _________________________
________________________________________________
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No type lines ______________ of cores are found in
______________
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AFIS
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______________ ______________ ______________ ______________ .
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AFIS uses automatic scanning devices that convert the image of a fingerprint into
digital ______________ that contain data showing ridged at their points of
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______________ (______________ endings) and the ______________ of ridges
into two ridges (______________)
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The computer can make ______________ of ______________ a second.
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In its first year of operation AFIS conducted 5,514 ______________ fingerprint
searches and achieved 1,001 identifications.
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Methods of detection
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Three kinds of ______________ scene prints
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______________ prints- are made by fingers contacting a ______________
surface such as blood or paint.
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______________ prints- prints left on soft ______________ such as wax or
putty.
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______________ prints- transfer of oils and sweat to the surface of an
object.
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There are multiple methods in detecting a ______________ print.
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The method of lifting usually depends on the ______________ being investigated.
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______________ prints deposited on hard and nonabsorbent surfaces (e.g., glass,
mirror, tile, and painted wood) are preferably developed by the application of a
______________.
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Prints on ______________ surfaces (e.g., papers, cardboard, and cloth) generally
require treatment with a ______________.
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Examiners use various chemical methods to visualize ______________ prints on
porous surfaces, such as iodine fuming, ninhydrin, and Physical Developer.
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Ninhydrin reacts chemically with trace amounts of ______________ acids present
in latent prints to produce a purple-blue color
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Super Glue® fuming develops ______________ prints on nonporous surfaces, such as
metals, electrical tape, leather, and plastic bags.
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A device called the ______________ Ultraviolet ______________ System (RUVIS)
can aid in the detecting of latent fingerprints, without chemicals or powder.
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Once located, the crime scene ______________ can develop the print in the most
appropriate fashion.
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Preservation
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Visualized ______________ print
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Permanently preserved
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______________ comparison
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Possible use as ______________ ______________
______________ must be taken
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Before any attempts at preservation
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small object: preserve in its ______________.
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large immovable objects
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developed with a ______________
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“____________” with a broad adhesive tape.
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tape placed on properly labeled card
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good background contrast with the powder
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Digital imaging
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Picture ______________ into digital computer file
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Help of digital imaging software
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Enhanced for the most ______________ and comprehensive analysis
Compare function
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Two ______________ side by side
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Allows the examiner to chart the common features on both images
______________
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