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Define forensics science.

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Title: Define forensics science.


1
  1. Define forensics science.
  2. When did fingerprinting identification come
    about?
  3. When was the first polygraph used?
  4. When was the FBI created?
  5. When did the fingerprinting become computerize?

2
  • 1.What were the names of the victims in the OJ
    Simpson case?
  • What pieces of evidence was there to link OJ to
    the crime scene.
  • What two pieces of evidence finally convicted Ted
    Bundy?

3
  • What are the two layers of the skin?
  • Which layer is alive?
  • Which layer do fingerprints come from?
  • What are the three most common fingerprints?
  • Name and describe any three points on a
    fingerprint.

4
  • What percent of finger prints are whorled?
  • Name and describe the four types of whorled
    fingerprints.
  • What is the most common type of finger print?
  • Name and describe the two types of looped
    fingerprints.

5
  • Name the type of surfaces that dusting, iodine
    super glue fuming is best used for?
  • How many points are needed for a positive
    identification?

6
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7
  • Sherlock Holmes, Perry Masons, Law and Order and
    CSI. (Jobs like those depicted in C.S.I. don't
    exist. Make sure you have realistic expectations
    before diving in).
  • Forensic science may generally be defined as the
    application of scientific, technical, or other
    specialized knowledge to assist courts in
    resolving questions of fact in civil and criminal
    trials.
  • forensic biology (DNA, blood, body fluids, etc.)
  • fingerprints
  • hair

8
History Of Forensics
  1. Begins in BC with fingerprints in early painting
    of prehistoric humans.
  2. 1784 John Toms was convicted of murder on the
    basis of the torn edge of wad of newspaper in a
    pistol matched the remaining piece in his pocket.
  3. 1813 Mathiew Orfila father of modern toxicology
    developed tests for the presence chemicals in the
    blood and is also credits with the first attempt
    to use a microscope in the assessment of blood
    and semen stains.
  4. 1835 Henry Goddard first to use a bullet
    comparison to catch murder
  5. 1879 Virchow first to use hair and recognize its
    limitations.
  6. 1884 Alfred Dreyfus was convicted of treason in
    France based on hand writing.
  7. 1901 Sir Edwards Richard Henry Fingerprint
    identification

9
  • 8. 1901 Henry Deforrest pioneered the first
    systematic use of fingerprints in the US.
  • 9. 1904 Oskar and Rudolf Adler developed a
    presumptive test for blood.
  • 10. 1921 John Larson and Leonard Keeler designed
    the first portable polygraph.
  • 11. 1924 August Vollmer first police crime lab in
    LA.
  • 12. 1932 FBI was created.
  • 13. 1984 Sir Alec Jefferys developed the first
    DNA profiling test.
  • 14. 1986 First case to use DNA to solve a crime
  • 15. 1996 FBI computerize Searches for Fingerprint
    database.

10
The Trial of the Century
  • Besides his Hall of Fame career, Simpson is
    infamous for having been tried for the murder of
    ex-wife Nicole Brown Simpson and her friend
    Ronald Goldman in 1994. He was acquitted in
    criminal court in 1995 after a lengthy, highly
    publicized trial.
  • In 1997, Simpson was found liable for their
    deaths in civil court, but to date has paid
    little of the 33.5 million judgment
  • He gained further notoriety in late 2006 when he
    wrote a book titled If I Did It. The book, which
    purports to be a first-person fictional account
    of the murder had he actually committed it, was
    withdrawn by the publisher just before its
    release.
  • The book was later released by the Goldman family
    and the title of the book was expanded to If I
    Did It Confessions of the Killer).
  • www.cnn.com/US/OJ/suspect/index.html

11
Evidence linking him to the murders.
  • DNA of Nicole Brown, Ronald Goldman, OJ Simpson
    was found at the scene.
  • Shoe prints found at the crime scene were from a
    size 12 Bruno Magli shoe, and bloody shoe
    impressions on the Ford Bronco carpet was
    consistent with a Bruno Magli shoe.
  • Simpson wore a size 12 shoe.

12
Ted Bundy
  • Theodore Robert 'Ted' Bundy (November 24, 1946
    January 24, 1989) was an American serial killer.
  • Bundy raped and murdered scores of young women
    across the United States between 1974 and 1978.
  • After more than a decade of vigorous denials,
    Bundy eventually confessed to 29 murders,
    although
  • he actual total of victims remains unknown.
    Typically, Bundy would rape his victims, and then
    murder them by bludgeoning, and sometimes by
    strangulation. He also engaged in necrophilia.
  • In stark contrast to the brutality of his crimes,
    Bundy was frequently described as educated and
    charming. His friends and acquaintances would
    remember him as a handsome and articulate young
    man.

13
Ted Bundy Time Line
  • January 4 - July 14,1974 Washington State
  • October 2, 74 May 6,1975 Utah State
  • Arrested August 16, 1975 Escaped from Aspen Jail
    by jumping from the library, found 8 days latter
    driving a car weaving in and out of traffic.
  • Escaped again in December 30, 1977
  • Bundy crawled over to a spot directly above the
    jailer's linen closet the jailer and his wife
    were out for the evening dropped down into the
    jailer's apartment, and walked out the door.
  • January 15 February 9 1978 Florida State (Chi
    Omega) - Bundy traveled to Lake City, Florida.
    While there, he abducted, raped, and murdered
    12-year-old Kimberly Leach, throwing her body
    under a small pig shed.

14
  • Two pieces of evidence proved crucial.
  • First, Chi-Omega member Nita Neary, getting back
    to the house very late after a date, saw Bundy as
    he left, and identified him in court.
  • Second, during his homicidal frenzy, Bundy bit
    Lisa Levy in her left buttock, leaving obvious
    bite marks. Police took plaster casts of Bundy's
    teeth and a forensics expert matched them to the
    photographs of Levy's wound. Bundy was convicted
    on all counts and sentenced to death.

15
Oklahoma City Bombing
  • April 19, 1995 aimed at the Alfred P. Murrah
    Federal Building, a U.S. government office
    complex in downtown Oklahoma City, Oklahoma. The
    attack claimed 168 lives and left over 800
    injured.
  • Timothy McVeigh arrest 90 minutes later from a
    vin number from a bomb car.
  • Teeth from victims helped identified 25 of the
    bodies.

16
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17
Madrid Bombings
  • Three of the trains set off from Alcala de
    Henares, about 12km to the east of Madrid. The
    fourth originated from Guadalajara, but passed
    through the station en route for the city.
  • On the morning of 11 March 2004 (three days
    before Spain's general elections), killing 191
    people and wounding 2,050.
  • That afternoon, detectives looked more carefully
    at the white van. They collected fingerprints,
    and under the passenger seat they found a plastic
    bag with seven detonators matching the type used
    in the bombings

18
The Verdict
19
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20
History of Fingerprints
  • The oldest known documents showing fingerprints
    date from third century B.C. China.
  • In ancient Babylon (dating back to 1792-1750
    B.C.), fingerprints pressed into clay tablets
    marked contracts.
  • The earliest written study (1684) is Dr.
    Nehemiahs paper describing the patterns he saw
    on human hands under a microscope, including the
    presence of ridges.
  • In 1788, Johann Mayer noted that the arrangement
    of skin ridges is never duplicated in two
    persons. He was probably the first scientist to
    recognize this fact.

21
History of Fingerprints
  • 5. Nine fingerprint patterns were described
    in 1823 by Jan Evangelist Purkyn.
  • 6. Sir William Herschel (shown at the right), in
    1856, began the collection of fingerprints and
    noted they were not altered by age.
  • 7. Alphonse Bertillon created a way to identify
    criminals that was used in 1883 to identify a
    repeat offender.
  • 8. In 1888, Sir Francis Galton (shown at the
    right), and Sir Edmund Richard Henry, developed
    the fingerprint classification system that is
    still in use in the United States.

22
  • In 1686, Marcello Malpighi, a professor of
    anatomy at the University of Bologna, noted in
    his treatise ridges, spirals and loops in
    fingerprints.
  • In 1823, John Evangelist Purkinje, a professor of
    anatomy at the University of Breslau, published
    his thesis discussing 9 fingerprint patterns.
  • In 1882, Gilbert Thompson of the U.S. Geological
    Survey in New Mexico, used his own thumb print on
    a document to prevent forgery.
  • In Mark Twain's book, "Life on the Mississippi",
    a murderer was identified by the use of
    fingerprint identification.
  • Sir Francis Galton, a British anthropologist and
    a cousin of Charles Darwin, began his
    observations of fingerprints as a means of
    identification in the 1880's.
  • Juan Vucetich, an Argentine Police Official,
    began the first fingerprint files based on Galton
    pattern types.
  • Juan Vucetich made the first criminal fingerprint
    identification in 1892. He was able to identify
    Francis Rojas, a woman who murdered her two sons
    and cut her own throat in an attempt to place
    blame on another.
  • The Fingerprint Branch at New Scotland Yard
    (London Metropolitan Police) was created in July
    1901 using the Henry System of Classification.
  • First systematic use of fingerprints in the U.S.
    by the New York Civil Service Commission for
    testing. Dr. Henry P. DeForrest pioneers U.S.
    fingerprinting.
  • The New York State Prison system began the first
    systematic use of fingerprints in U.S. for
    criminals. 
  • 1905, U.S. Army begins using fingerprints.
  • 1907, U.S. Navy begins using fingerprints.
  • 1908, U.S. Marine Corps begins using
    fingerprints.
  • By 1946, the FBI had processed 100 million
    fingerprint cards in manually maintained files
    and by 1971, 200 million cards.
  • 2007, The largest AFIS repository  in America is
    operated by the Department of Homeland Security's
    US Visit Program, containing over 74 million
    persons' fingerprints, primarily in the form of
    two-finger records.

23
History of Fingerprints
  • Fingerprints offer an infallible means of
    personal identification. That is the essential
    explanation for their having supplanted other
    methods of establishing the identities of
    criminals reluctant to admit previous arrests.  
  • The science of fingerprint Identification stands
    out among all other forensic sciences for many
    reasons, including the following   
  • Has served all governments worldwide during the
    past 100 years to provide accurate
    identification of criminals. No two fingerprints
    have ever been found alike in many billions of
    human and automated computer comparisons. 
    Fingerprints are the very basis for criminal
    history foundation at every police agency.

24
  • Established the first forensic professional
    organization, the International Association for
    Identification (IAI), in 1915.
  • Established the first professional
    certification program for forensic scientists,
    the IAI's Certified Latent Print Examiner
    program (in 1977), issuing certification to
    those meeting stringent criteria and revoking
    certification for serious errors such as
    erroneous identifications. 
  •  
  • Remains the most commonly used forensic
    evidence worldwide - in most jurisdictions
    fingerprint examination cases match or outnumber
    all other forensic examination casework
    combined.
  • Continues to expand as the premier method for
    identifying persons, with tens of thousands of
    persons added to fingerprint repositories daily
    in America alone - far outdistancing similar
    databases in growth.
  • Outperforms DNA and all other human
    identification systems to identify more
    murderers, rapists and other serious offenders
    (fingerprints solve ten times more unknown
    suspect cases than DNA in most
    jurisdictions).   

25
  • Other visible human characteristics change -
    fingerprints do not. In earlier civilizations,
    branding and even maiming were used to mark the
    criminal for what he was. The thief was deprived
    of the hand which committed the thievery. The
    Romans employed the tattoo needle to identify and
    prevent desertion of mercenary soldiers. 
  •  
  • Before the mid-1800s, law enforcement officers
    with extraordinary visual memories, so-called
    "camera eyes," identified previously arrested
    offenders by sight. Photography lessened the
    burden on memory but was not the answer to the
    criminal identification problem. Personal
    appearances change.
  • Around 1870, a French anthropologist devised a
    system to measure and record the dimensions of
    certain bony parts of the body. These
    measurements were reduced to a formula which,
    theoretically, would apply only to one person and
    would not change during his/her adult life.

26
  • This Bertillon System, named after its inventor,
    Alphonse Bertillon, was generally accepted for
    thirty years. But it never recovered from the
    events of 1903, when a man named Will West was
    sentenced to the U.S. Penitentiary at
    Leavenworth, Kansas. It was discovered that there
    was already a prisoner at the penitentiary at the
    time, whose Bertillon measurements were nearly
    the same, and his name was William West.
  • Upon investigation, there were indeed two men who
    looked exactly alike. Their names were Will and
    William West respectively. Their Bertillon
    measurements were close enough to identify them
    as the same person. However, a fingerprint
    comparison quickly and correctly identified them
    as two different people. (Per prison records
    discovered later, the West men were apparently
    identical twin brothers and each had a record of
    correspondence with the same immediate family
    relatives.)

27
What Are Fingerprints?
  • All fingers, toes, feet, and palms are covered in
    small ridges.
  • These ridges are arranged in connected units
    called dermal, or friction, ridges.
  • These ridges help us get or keep our grip on
    objects.
  • Natural secretions plus dirt on these surfaces
    leave behind an impression (a print) on those
    objects with which we come in contact.

28
What makes a fingerprint?
  • 1)  Ridge patterns and the details in small areas
    of friction ridges are unique and never repeated.
  • 2)  Friction ridges develop on the fetus in their
    definitive form before birth.
  • 3)  Ridges are persistent throughout life except
    for permanent scarring.
  • 4)  Friction ridge patterns vary within limits
    which allow for classification.
  • Identical twins have the same DNA configuration
    but they do not have identical friction ridge
    configuration.

29
The skin
  • There are approximately 2,700 ridge "units" per
    square inch of friction skin. 
  • The Epidermis (E) is stratified (layered), 
    squamous (flat) epithelial tissue 5 layers thick
    and...
  • The Dermis is much thicker than the epidermis and
    consists of two layers - the Papillary layer
    (DPL) an area of loose connective tissue
    extending up into the epidermis as dermal pegs
    (DP) and the deeper reticular layer (DRL).

30
Formation of Fingerprints
  • An animals external tissue (skin) consists of
    (a) an inner dermis and (b) an outer epidermis.
  • The creation of fingerprints occurs in a special
    layer (the basal layer) in the epidermis where
    new skin cells are produced.
  • Fingerprints probably begin forming at the start
    of the 10th week of pregnancy.
  • Because the basal layer grows faster than the
    others, it collapses, forming intricate shapes.

31
There are three main types of fingerprints
visible prints, latent prints and impressed
prints.
  • Visible prints are also called patent prints and
    are left in some medium, like blood, that reveals
    them to the naked eye. They can be when blood,
    dirt, ink or grease on the finger come into
    contact with a smooth surface and leave a
    friction ridge impression that is visible without
    development.
  • Latent prints are not apparent to the naked eye.
    They are formed from the sweat from sebaceous
    glands on the body or water, salt, amino acids
    and oils contained in sweat. The sweat and fluids
    create prints must be developed before they can
    be seen or photographed. They can be made
    sufficiently visible by dusting, fuming or
    chemical reagents.
  • Impressed prints are also called plastic prints
    and are indentations left in soft pliable
    surfaces, such as clay, wax, paint or another
    surface that will take the impression. They are
    visible and can be viewed or photographed without
    development.

32
Characteristics of Fingerprints
  • Forensic examiners look for the presence of a
    core (the center of a whorl or loop) and deltas
    (triangular regions near a loop).
  • A ridge count is another characteristic that
    distinguishes one fingerprint from another. The
    count is made from the center of the core to the
    edge of the delta.

33
Key points to fingerprints
  • Endings, the points at which a ridge stops
  • Bifurcations, the point at which one ridge
    divides into two
  • Dots, very small ridges
  • Islands, ridges slightly longer than dots,
    occupying a middle space between two temporarily
    divergent ridges
  • Ponds or lakes, empty spaces between two
    temporarily divergent ridges

34
Spurs, a notch protruding from a ridge Bridges,
small ridges joining two longer adjacent ridges
Crossovers, two ridges which cross each other
The core is the inner point, normally in the
middle of the print, around which swirls, loops,
or arches center. It is frequently characterized
by a ridge ending and several acutely curved
ridges. Deltas are the points, normally at the
lower left and right hand of the fingerprint,
around which a triangular series of ridges
center.
35
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36
Fingerprint Forensic FAQs
  • Can fingerprints be erased?
  • No, if, for example, they are removed with
    chemicals, they will grow back.
  • Is fingerprint identification reliable?
  • Yes, but analysts can make mistakes.
  • Is fingerprint matching carried out by computers
    in a matter of seconds?
  • No, but the FBIs Integrated Automated
    Fingerprint Identification System (IAFIS or AFIS)
    can provide a match in 2 hours for the prints in
    its Master File.

37
Types of prints
  • Arched Looped Whorled
  • 5 of Pop 65 of Pop 30 of Pop

38
Characteristics of Fingerprints
  • Basic patterns can be further divided
  • Arch patterns can be plain (4) or tented (1).
  • Whorl patterns can be central pocket (2), double
    loop (4), or accidental (0.01).
  • Even twins have unique fingerprints due to small
    differences (called minutiae) in the ridge
    patterns.

39
Whorled Finger prints
  • 30 of fingerprints are whorled.
  • 4 types of whorled patterns
  • 1. Accidental
  • 2. Plain
  • 3. Double loop whorled
  • 4. Central pocket

40
Looped finger prints
  • 60-65
  • 1. Radial Loop
  • 2. Ulnar Loop

41
Problems or disease with finger printing
42
Techniques For Lifting a Print
43
Dusting
  • Used on smooth, non-porous materials.
  • The area is lightly and carefully dusted with
    either a black or white powder, depending on the
    contrasting surface.
  • The dust is lifted with tape and set against a
    contrasting background.
  • The print is preserved via photography.

Fingerprint dusting in a lab
44
Iodine Fuming
  • Suspect material is placed in an enclosed
    cabinate along with iodine crystals.
  • The crystals are heated, and will sublimate (turn
    into a gas vapor).
  • The vapors cause the prints to visualize.

Fingerprint visualized with iodine fuming.
45
Chemical Treatment
  • Ninhydrin (triketohydrindene hydrate)- this
    chemical is sprayed onto a porous surface via an
    aerosol can. Prints begin to visualize an hour or
    two after application, although the process can
    be accelerated through heating the print.
  • Silver nitrate- silver nitrate is sprayed onto
    the porous surface and left to dry. Then it is
    exposed to ultraviolet light to visualize the
    prints.

Silver Nitrate spray bottle
46
Superglue Fuming
  • Used mainly on non-porous materials.
  • Superglue is placed on cotton and treated with
    sodium hydroxide.
  • Fumes can also be created by heating the glue.
  • The fumes and the object are contained in a
    closed chamber for up to six hours.
  • The fumes adhere to the print, visualizing it.

Fuming tank
47
Analysis of Prints
  • Prints are analyzed by looking for points of
    interest or minutiae.
  • If 8-16 match points are made, the fingerprints
    match.
  • Nowadays a computer can be used to assist this
    process of matching points.
  • Known criminals are fingerprinted, and the prints
    are filed away in a database known as the
    Integrated Automated Fingerprint Identification
    System. If a print is found at a crime scene,
    investigators look for a match in the database.

48
Fingerprint Forensic FAQs
  • How are latent fingerprints collected?

49
The Future of Fingerprinting
  • New scanning technologies and digitally
    identifying patterns may eliminate analytical
    mistakes.
  • Trace elements of objects that have been touched
    are being studied to help with the identification
    of individuals.
  • To help with identification, other physical
    features such as eyes and facial patterns are
    also being studied.

50
. . . . . . . . . . . . . . . . . Summary
  • Fingerprints have long been used for
    identification, and in the mid-1800s were
    recognized as unique to each person.
  • Three main groups include arches, whorls, and
    loops.
  • Basic analysis includes looking for cores,
    deltas, and making a ridge count.
  • Investigators search for patent, plastic, and
    latent prints.
  • Dusting with powders or using special chemicals
    can make latent fingerprints visible.
  • New developments may eliminate errors by
    analysts.
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