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Chapter 8



Fingerprints
History
   Alphonse Bertillon: anthropometry


   1892 Francis Galton-Finger Prints


-UK-fingerprinting -supplement to Bertillon system
History
 1850’s:
-photographing inmates

  Allan Pinkerton:
-rogues gallery

 NYPD Detective Thomas Byrnes:
-NYPD gallery-“mug” shots
Mug shots
     NYPD: original
      collection of mug
      shots
History
  Will West/William West (1903)
-2 inmates/same anthropometrical measurements
-fingerprints ID’d them

  1904 World’s Fair:
-fingerprinting introduced to US Police
Mug shots
     Collection of mug shots
Mug Shots
     John Dillinger
Mug Shots
     Alphonse Capone
Mug Shots
     James Brown
Mug Shots
     Nick Nolte
Fingerprints


What are fingerprints?

   Friction ridge skin pattern



   ridges (hills)/furrows
    (valleys)
                                  Black = Ridges
                                  White = Valleys
Fingerprints

What are fingerprints?

   embryonic development

   genetics, detail-random
Fingerprints


3 types
1.   Visible – dirt/grease/blood
Fingerprints


3 types
2.   Impression – soft material (butter, putty,
     tar)
Fingerprints

3 types
3.   Latent – requires processing
Fingerprints > Analysis


invisible components
-sweat glands secrete onto fingers/palms

-
Sweat contains:
       Inorganic ions (Na+, Cl -)      Lipids
       Proteins, amino acids           Other
Visible prints
Fingerprint Principles
    3 principles:

1.   Uniqueness:

2.   Permanence:

3.   Patterns:
Principle One
   UNIQUENESS:

-no two people identical

-identification-ridge characteristics (minutiae)

-> 150 minutiae on average finger
Principle One
        DO NOT WRITE DOWN!
   Points? How many required for ID in US Courts?

-“no valid basis exists for requiring a predetermined
   minimum number of friction ridge characters which must
   be present in two impressions in order to establish
   positive identification”

-sufficient number of friction ridge details present for
   conclusion 100%
Principle One
   Conclusions:

   Match
   no match
   inconclusive
Principle Two
   PERMANENCE:
   Epidermis-outer layer

   Dermis-inner layer

   Form in womb/unchanged for life
PRINCIPLE THREE
 Patterns:

-classification/filing

-3 patterns

DO NOT CONFUSE PATTERNS WITH
 PRINCIPLES!!!
Principle Three
Pattern 1:


Loop:
-60 %
Principle
  Three
Pattern 2:

Whorls:

35%
Whorls
Double Loop Whorl
                        Accidental Whorl
Principle Three
   ARCHES:
   Least common

   5%
   a. Plain
   b. Tented
Arches
   Plain         Tented
Developing Prints
   Surface=substrate

   Hard/nonabsorbent: powder


   Porous: chemical
Detecting Prints
 Powders:
-adhere to perspiration/body oils

  Iodine fuming:
-iodine crystals release vapors
Detecting Prints
 Ninhydrin:
-amino acids/purple-blue



  Super Glue®:
-
 cyanoacrylate ester
Developing Prints
   Fluorescence:

-chemicals-fluorescence -high-intensity light


-photographs must be taken before attempts at
  lifting
Fingerprints > Analysis


Physical Development: Dusting


    Powder adheres


      Brush and Powder
Fingerprints > Analysis


Physical Development: Dusting




        Magnetic Brush
         and Powder
Powder
   Latent print developed
     with powder
Powder
    Print in dust:
   Left-actual print
   Middle-developed with
     powder
   Right-photographed
Powder
            Shell casing
Fingerprints > Analysis

Chemical Development:
2.       Iodine Fuming
         Iodine reacts w/ lipid
          components
         Fuming wand/chamber




                                   Dirty Brown Color
Fingerprints > Analysis

Chemical Development:
3.       Ninhydrin
          Reacts with amino acids; purple color
          Painted or sprayed on area
          Heated to react
Development
      Fingerprints on the
        inside of a rubber
        glove
Development
      Fingerprints developed
        on plastic bag
Development
      Inside of rubber gloves
        treated with ninhydrin
Development
         Ninhydrin
Development
         Ninhydrin-Note initials
          at top-CHAIN OF
          CUSTODY
Development
      Super glue developed
        prints
Developing
     Latent prints visulaized
       using fluorescent
       powder
Developing
     Different colored
       fluorescent powder
Development and Collection
 Scene or Lab?



 Small objects:
-preserved/transported

 Large immovable objects:
-develop prints/lift
Digital Imaging
 Digital imaging:
-picture converted-digital computer file

 Compare function:
-images side by side
Fingerprints > Collection


Collection of prints:
Sometimes a photograph will be the only
  permanent record.
Fingerprint Kit
Fingerprints


How are fingerprints analyzed?




    Categorized by pattern and minutiae
Fingerprints

How are fingerprints analyzed?
Patterns




        Loop   Whorl      Arch
Fingerprints

How are fingerprints analyzed?
Minutiae




               Bifurcation            Ridge Ending

    Dot                      Island
AFIS
   Computer scans/digitally encode fingerprints

-classifying /retrieving

-digital minutiae

-list of file prints

-examined by expert
Old system of fingerprints
Fingerprints




               Computer software
               compares the
               location of these
               minutiae.
AFIS
  AFIS highlights all the
   identifiable minutia.
Madrid Bombing Timeline
   March 11, 2004
    – Terrorists bomb several trains in Madrid,
      Spain
   March 13, 2004
    – LPU receives electronic transmission of
      digital
       images (no info, scale, etc.)
       8 latent prints
       Known exemplars
   March 19, 2004
Madrid
   April 13, 2004
    – Spanish National Police (SNP) issues
      ‘negativo’ report regarding latent print
   April 21, 2004
    – LPU rep travels     to Spain to provide basis of
      identification to   SNP
Madrid
   May 6, 2004
    – Brandon Mayfield arrested by FBI Portland
   May 19, 2004 (in California)
    – Defense expert verifies FBI identification
   May 19, 2004
    – SNP informs FBI they have identified the
      latent fingerprint with another individual
   May 20, 2004
    – Judge releases Mayfield
MADRID BOMBING

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Ch 8 fingerprints

Editor's Notes

  1. Alphonse Bertillon: Anthropometry/Father of criminal identification. In 1892 Francis Galton published his classic textbook Finger Prints . At Galton’s insistence, the British government adopted fingerprinting as a supplement to the Bertillon system. The next step was the creation of classification systems capable of filing many thousands of prints in a logical and searchable sequence.
  2. 1850’s: Prisons began photographing inmates for ID purposes. 1880’s: Gained popularity after Kodak camera developed. Allan Pinkerton: Detective Agency-Rogues Gallery. NYPD Detective Thomas Byrnes: Developed NYPD gallery. “ mug” shots
  3. In 1903, Will West/William West incident. Fingerprinting clearly distinguished them. After the Will West incident NY Civil Service began fingerprinting applicants (1901). 1904 World’s Fair: Scotland Yard introduces fingerprinting to US Police Forces
  4. Fingerprints: Reproduction of friction skin ridges found on the palm side of the fingers and thumbs. The basic principles: 1. Uniqueness: individual characteristic; no two fingers possess identical ridge characteristics 2. Permanence: fingerprints remain unchanged 3. Patterns: general ridge patterns that permit them to be systematically classified.
  5. Mathematically, the probability for the existence of two identical fingerprint patterns in the world’s population is extremely small. Besides theoretical calculations, of the millions upon millions of individuals who have had their prints classified, no two fingerprints have been found to be identical. The individuality of a fingerprint is not determined by its general shape or pattern, but by the careful study of its ridge characteristics, known as minutiae. It is the identity, number, and relative location of these minutiae that imparts individuality to a fingerprint. There are as many as 150 minutiae on the average finger.
  6. Points? How many required for ID in US Courts? After a three year study, it was determined that “no valid basis exists for requiring a predetermined minimum number of friction ridge characters which must be present in two impressions in order to establish positive identification.” Sufficient number of friction ridge details present for conclusion 100%
  7. Conclusions: -Subject made the print -Subject could not have made the print -Print had insufficient detail to be evaluated In a judicial proceeding, an expert must demonstrate a point-by-point comparison in order to prove the identity of an individual.
  8. Epidermis: outer layer of the skin Dermis: inner layer of the skin. Dermal papillae: layer of cells between the epidermis and dermis/determines form and pattern of the ridges on the surface of the skin. Develops in the fetus and remains unchanged throughout life. Each skin ridge is populated with pores leading to sweat glands from which perspiration is deposited on the skin. Once the finger touches a surface, perspiration, along with oils that may have been picked up by touching the hairy portions of the body, is transferred onto that surface, leaving the finger’s ridge pattern (a fingerprint).
  9. ARCHES: Least common type of pattern Only 5% of all patterns 2 subcategories: a. Plain b. Tented
  10. Latent prints deposited on hard and nonabsorbent surfaces (e.g., glass, mirror, tile, and painted wood) are preferably developed by the application of a powder; whereas prints on porous surfaces (e.g., papers, cardboard, and cloth) generally require treatment with a chemical. Examiners use various chemical methods to visualize latent prints on porous surfaces, such as iodine fuming, ninhydrin, and Physical Developer. Super Glue ® fuming develops latent prints on nonporous surfaces, such as metals, electrical tape, leather, and plastic bags. Development occurs when fumes from the glue adhere to the print, usually producing a white latent print
  11. A devise called the Reflected Ultraviolet Imaging System (RUVIS) can aid in the detecting of latent fingerprints, without chemicals or powder. Once located, the crime scene investigator can develop the print in the most appropriate fashion. Powders, available in a variety of colors, can be applied with a brush or magnetic wand, and adhere to perspiration and/or body oils of the print. Iodine fuming involves heating iodine crystals that cause vapors which combine with latent prints to make them visible. Iodine prints are not permanent and will fade, making it necessary to photograph the prints immediately.
  12. Ninhydrin reacts chemically with trace amounts of amino acids present in latent prints to produce a purple-blue color. Physical Developer is a silver nitrate-based reagent used to develop prints when other chemical methods are ineffective. Super Glue ® is approximately 98 to 99 percent cyanoacrylate ester, a chemical that actually interacts with and visualizes a latent fingerprint. Super Glue fuming can be accomplished by using either a fuming chamber (for up to six hours) or a handheld wand that heats a small cartridge containing cyanoacrylate.
  13. The high sensitivity of fluorescence serves as the underlying principle of many of the new chemical techniques used to visualize latent fingerprints. Fingerprints are treated with chemicals that would induce fluorescence when exposed to lasers, or high-intensity light sources (“alternate light sources”) such as quartz halogen, xenon arc, or indium arc light sources. Once the latent print has been visualized, it must be permanently preserved for future comparison and for possible use as court evidence. A photograph must be taken before any further attempts at preservation are made.
  14. If the object is small enough to be transported without destroying the print, it should be preserved in its entirety. Prints on large immovable objects that have been developed with a powder can best be preserved by “lifting” with a broad adhesive tape. Then, the tape is placed on a properly labeled card that provides a good background contrast with the powder.
  15. Digital imaging is the process by which a picture is converted into a digital computer file. With the help of digital imaging software, fingerprints, which are often not in perfect condition, can now be enhanced for the most accurate and comprehensive analysis. An important and useful tool, especially for fingerprint identification, is the compare function that places two images side by side and allows the examiner to chart the common features on both images simultaneously.
  16. The heart of AFIS technology is the ability of a computer to scan and digitally encode fingerprints so that they can be subject to high-speed computer processing. 1999 by FBI AFIS aids in classifying and retrieving fingerprints by converting the image of a fingerprint into digital minutiae that contain data showing ridges at their points of termination (ridge endings) and their branching into two ridges (bifurcations). When the search is complete (a computer can make thousands of comparisons per second), the computer produces a list of file prints that must be examined by a trained fingerprint expert.