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Chapter 14 - Fingerprints
4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Fingerprints Section 1 Objectives Name those individuals who have made significant contributions to the acceptance and development of fingerprint technology. Define ridge characteristics. Explain why a fingerprint is a permanent feature of the human anatomy. 4/19/2019 Created by C Ippolito February 2008
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Personal Identification
Bertillon System anthropometry system of precise body measurements Portrait parle detailed description of subject Photographs full length profile sherlockholmes.stanford.edu/print_issue3.html 4/19/2019 Created by C Ippolito February 2008
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Bertillon Card 11 measurements dimensions of bony parts of the human anatomy Description surface markings disease accident deformity artificial disfigurement moles warts scars tattooing Photos 4/19/2019 Created by C Ippolito February 2008
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Early Fingerprint Usage
Ancient China sign legal documents W. Herschel handprint on Indian contracts H. Faud “skin ridges” can be used to identify criminals 4/19/2019 Created by C Ippolito February 2008
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Early Fingerprint Classification
F. Galton (1892) “Fingerprints” 3 patterns loops arches whorls J. Vucetich (1897) refined system still used E. Henry (1897) system adopted by Scotland Yard 4/19/2019 Created by C Ippolito February 2008
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Adoption of Fingerprinting
NYC Civil Service Commission 1901 for personal ID St. Louis World’s Fair 1904 introduction by Scotland Yard FBI established 1924 now largest collection in world 4/19/2019 Created by C Ippolito February 2008
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Individuality of Fingerprints
ridge characteristics (minutiae) used to match prints (8-16) cross over core bifurcation ridge ending island (dot) delta pore 4/19/2019 Created by C Ippolito February 2008
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Fingerprints Unchangeable
formed by ridges of dermal papillae 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Fingerprints Section 2 Objectives List the three major fingerprint patterns and their subclasses. 4/19/2019 Created by C Ippolito February 2008
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General Ridge Patterns
Three classes: loop whorl arch 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Loop Pattern ulnar loop ridges open towards pinkie finger ridge loop ridges open towards thumb core center of the pattern type lines diverging ridges surround pattern 4/19/2019 Created by C Ippolito February 2008
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Whorl Pattern circular ridges type lines & two deltas Four types plain central pocket double loop accidental plain and central pocket – ridge goes completely around plain – imaginary line from deltas touches “circular ridge” central pocket – line does not touch circular ridge 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Arches simplest ridges enter one side exit from opposite side Two forms plain tented 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Fingerprints Section 3 Objectives Classify a set of fingerprints by the primary classification of the Henry system. Describe the concept of an automated fingerprint identification system. 4/19/2019 Created by C Ippolito February 2008
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Henry System of Classification
fingers assigned # by position ridge patterns assigned numerical value arranged into a fraction i.e. LWAALALWLA pattern series (1-10) 4/19/2019 Created by C Ippolito February 2008
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FBI Classification System
pairs up fingers whorl on 1st pair = 16 whorl on 2nd pair = 8 whorl on 3rd pair = 4 whorl on 4th pair = 2 whorl on last pair = 1 arches and loops = 0 add 1 to numerator and denominator left hand – LWAAL (pinky to thumb) right hand – ALWLA (thumb to pinky) 4/19/2019 Created by C Ippolito February 2008
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Automated Fingerprint Identification System (AFIS)
classification and retrieval by computers scanner converts print to digital minutiae relative position and orientation determined set of prints can be compared to 500,000 sets in 8/10 second 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
How AFIS works filters out imperfections create graphic representation of ridge endings, bifurcations and directions compared side by side on screen 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Fingerprints Section 4 Objectives Explain what is meant by visible, plastic, and latent fingerprints. List the techniques for developing latent fingerprints on nonporous objects. Describe chemical techniques for developing prints on porous objects. Describe the proper procedures for preserving a developed latent fingerprint. Explain how a latent fingerprint image can be enhanced by digital imaging. 4/19/2019 Created by C Ippolito February 2008
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Crime Scene Fingerprints
Visible Prints ridges in contact with a colored material blood, paint, grease, ink Plastic Prints ridge impressions left on soft material putty, wax, soap, dust Latent Prints (invisible) ridge impressions left by oils and perspiration 4/19/2019 Created by C Ippolito February 2008
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Locating and Developing Fingerprints
type of surface determines how to make visible hard nonabsorbant surfaces glass, mirror, tile, painted wood soft porous surfaces paper, cardboard, cloth Reflected Ultraviolet Imaging System (RUVIS) locates prints using UV light 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Fingerprint Powders nonabsorbant surfaces adhere to oil/perspiration residue applied with brush aluminum powder (gray) carbon powder (black) magnetic powder 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Iodine Fuming Sublimation solid changes directly from solid to gas iodine vapors combine with oils temporary photographed fixed by spraying with starch 4/19/2019 Created by C Ippolito February 2008
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Ninhydrin Ninhydrin (triketohydrindene hydrate) reagent reacts with amino acids in perspiration 0.6 percent solutions used sprayed on porous material DFO (1,8 diazafluoren-9-one) used on porous surfaces w/alternate light source 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Physical Developer contains silver nitrate well on porous materials that were wet used when iodine or ninhydrin give no results 4/19/2019 Created by C Ippolito February 2008
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Superglue (cyanoacrylate) Fuming
works with nonporous surfaces metals, plastic bags, electric tape etc fumes by adding to glue to cotton and NaOH heating wand w/cartridge used at scene 4/19/2019 Created by C Ippolito February 2008
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Created by C Ippolito February 2008
Laser/LED Lights cause components of perspiration to fluoresce emit visible light like luminol and blood rxn 4/19/2019 Created by C Ippolito February 2008
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Preservation of Fingerprints
digital imaging picture converted into pixels capable of analysis fingerprint tape lift developed print with tape 4/19/2019 Created by C Ippolito February 2008
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