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CHE 113 1
Chapter 17:
Questioned Documents
Voice Analysis
(Forensic Linguistics)
CHE 113 2
Language
Sometimes, however, the manner that we
choose to communicate may be almost as
important as the thoughts themselves.
development of ways in which to extend
and expand our ability to communicate with
others far away
as our needs and desires grew, so did the
development of more complex forms of
language and communication.
The study of language is referred to as
linguistics
CHE 113 3
Written Word
Handwriting, and later printing, provided
humans with the ability to communicate easily
across space and time.
graphic forms of communication developed
long ago and allowing individualism
handwriting holds information quite
personal beyond the actual words.
– these graphic forms of communication and
expression extend to include both traditional
forms of art and imagery as well as
photographic, video and digital art.
CHE 113 4
Written Word
CHE 113 5
Written Word
We are often greatly influenced by
photographic and video images with almost
instant access to visual media produced from
across the world.
given the availability and ease of use of
computer photographic and video altering
software, how do we know that what we are
looking at is real
a key forensic question that is increasingly
being asked is whether images are authentic
or somehow modified?
CHE 113 6
Questioned Documents
(Top) a composite photograph of Sen. John
Kerry seemingly sharing the podium with
Jane Fonda at a 1970s anti-war rally. The
picture appeared during Kerry’s 2004
presidential run.
CHE 113 7
Questioned Documents
The top composite was actually made up of a
June 1971 image of Kerry preparing to speak
to a Peace Rally in New York (Bottom left)
with a August 1972 image of Jane Fonda from
a Miami Beach, Florida political rally (bottom
right)
CHE 113 8
Questioned Documents (QD)
Documents form the basis of a large part of
our communication, providing permanent
records of our thoughts, actions and
transactions.
Recording legal, personal, and financial
information.
Forgery is defined as the act of preparing or
altering a document, signature, financial
certificate, work of art, or other valued item with
the intention to defraud, damage or cheat
CHE 113 9
Questioned Documents (QD)In forensic science, the term “questioned
document” refers to any document over which
there is some legal dispute regarding its
origin, authenticity, or authorship.
Such documents might include financial checks,
currency, wills, anonymous letters, agreements,
passports, personal identification records,
receipts, and many others.
The field encompasses many components of
document analysis but includes handwriting
analysis, signature authenticity, and examination
of a variety of printed materials.
CHE 113 10
Questioned Documents (QD)the “Wacker Case,” one of
the most famous frauds in art
history…
The case involved 33 works
allegedly painted by Vincent
van Gogh and helped foster the
development of scientific
techniques, many based on
chemistry, to examine
paintings at the molecular level
and determine their
authenticity.
CHE 113 11
Questioned Documents (QD)Frank Abignale Jr., who
successfully performed cons
worth millions of dollars
before his 19th birthday!
He managed to get away with
it by posing as a Pan American
World Airways pilot, a
Georgia doctor, and a
Louisiana parish prosecutor.
he become so skillful that the
FBI turned to him to help in
catching other check forgers!
CHE 113 12
Questioned Documents (QD)
Physical Evidence :
– Determine if authentic (non forgery).
– Determine if a document has be altered.
– Match sample with suspect.
CHE 113 13
Questioned Documents
Physical examinations in QD involves scrutiny of
surfaces and other items. Paper is the most typical
surface examined. Examiners may focus on one or
more of the following:
– Something on the surface, such as handwriting,
typewriting, alterations, or obliterations.
– Something in the surface, such as indented writing,
watermarks, or safety fibers.
– Damage to the surface, such as torn edges, moisture, or
charring.
CHE 113 14
Hand Writing Analysis
Not all handwriting is identifiable to a specific writer or writers.
Examination of handwriting characteristics can sometimes result in determining the origin or authenticity of questioned writing.
Traits such as age, sex, personality, or intent cannot be determined from handwriting examinations.
– Personality traits do not normally show up until the 4th grade when writing becomes a subconscious skill
Handwriting comparisons based on the principle that no two people write exactly alike and that characteristics reoccur throughout every person's writing.
A combination of characteristics is unique to every individual and is used by document examiners for comparison.
CHE 113 15
Hand Writing Analysis
Individualizing features are often divided into four main
categories:
form – includes handwriting style, shape of the letters,
slope and line locations, rhythm of the writing, and size of
writing
– block, script, or cursive
arrangement – includes spacing of letters
quality – includes pressure and thickness
content. - includes grammar, spelling, and syntax
CHE 113 16
Hand Writing Analysis
Handwriting Styles
CHE 113 17
Hand Writing Analysis
Handwriting Slope
CHE 113 18
Hand Writing Analysis
Handwriting Form– Handwriting style (block, cursive, etc.)
– Shape of the letters
– Slope and line locations of the writing
– Rhythm of the writing
– Size of the writing
Arrhythmic
handwriting
of mass-
murder
Charles
Manson
CHE 113 19
Hand Writing Analysis
sample copybook in the
Zaner-bloser writing
style commonly taught
beginning in about the
1960s
CHE 113 20
Hand Writing Analysis
Handwriting examples based on where the author first learned to write.
CHE 113 21
Hand Writing Analysis
Handwriting analysis deals with determining
the authorship of a document.
Were two documents written by the same hand
(identification) or were the two documents written
by different people (forgery).
– comparison of the questioned document with
handwriting examples known to have been written by
the purported author of the document.
– Nine categories
CHE 113 22
Hand Writing Analysis
A definite opinion is not always possible when conducting a handwriting comparison. Reasons for an inconclusive result include:
– The questioned writing is limited.
– The known writing is limited in amount,
comparability, or both.
– The writing is not naturally prepared.
CHE 113 23
Hand Writing Comparison
Compare Exemplar with Questioned Document
CHE 113 24
Levels of individualization– identification (highest degree of confidence that the handwriting
belonged to the ascribed author)
– highly probable
– probable
– indications (some evidence for similarities exist but the
connection is not relatively weak)
– no conclusion (unable to make a determination)
– indications did not (some dissimilarities exist but the evidence is
not strong)
– probably did not (the two documents likely did not come from
the same author),
– strong probability did not (almost certain that the two documents
do not match),
– elimination (the two documents were definitely written by
different authors
Hand Writing Lab
CHE 113 25
CHE 113 26
Important tool for document examiners
Two compound microscopes combined into one unit
When viewer looks through the eyepiece, a field divided into two equal parts isobserved
Bullet comparisons- requires reflective light
• Hair & Fiber comparisons
• Questioned documents
Comparison Microscope
CHE 113 27
Comparison Microscope
Split-image comparison of banknotes:
on the left the original, on the right the forgery
CHE 113 28
Counterfeiting
Creating
fraudulent legal
documents (e.g.,
money)
CHE 113 29
Counterfeiting
$50 Bill shows the words “The United States of
America” printed on Pres. Grant’s collar
VICE NEWS Doc
https://www.youtube.com/watch?
v=4RoZrtBijRY
CHE 113 30
CHE 113 31
Hitler Diaries
Hitler Diaries…
The Big "Discovery"
In April 1983, the popular West German magazine Stern made a shocking announcement that sparked passionate debates throughout the world and temporarily challenged historical views concerning Germany’s most notorious ex-chancellor. The periodical claimed that 62 handwritten volumes of secret diaries allegedly written by the founder of the Third Reich, Adolf Hitler, had been discovered in East Germany. According to Charles Hamilton’s book, The Hitler Diaries, the volumes were reported to be one of the most-significant, historical discoveries in recent history. However, time proved the manuscripts instead were one of the biggest hoaxes of the century.
Hitler Diaries…
…in an effort to set history straight, it was decided that the diaries would undergo more rigorous testing by scientists and scholars. It didn’t take long for them to determine that the diaries were, in fact, elaborate forgeries and by no means the work of Hitler. Moreover, it was discovered that during the initial analysis by handwriting experts, the purported “original” documents that the diaries were compared against were also forgeries concocted by the same individual. Eventually, the world learned the identity of the mastermind behind the elaborate hoax, a petty criminal and Hitler enthusiast named Konrad Kujau. He later earned the reputation as one of the century’s most notorious forgers, who successfully fooled millions with his reinvented account of history.
CHE 113 34
Questioned Documents
Watermarks: A translucent design impressed on paper during manufacture and visible when the paper is held to the light.
CHE 113 35
Questioned Documents
Examination of indented writing (writing from pressure on underlying pages) using oblique lighting or electrostatic detection apparatus.
– Typewriting comparison and reconstruction may establish that a particular typewriter was used to type a particular document, or suggest a particular brand of typewriter was used.
– Determination of text from used ribbons.
– Examination of altered documents including the detection of additions, erasures, obliterations, and changes.
– Determination of fake documents including checks, wills, and bonds.
CHE 113 36
Questioned Documents
Oblique Lighting -– Photographic
techniques to enhance indented writing (top) using side lighting and special film. Bottom shows the apparent bank robbery note that was produced from the indentations in the paper.
CHE 113 37
Questioned Documents
Electrostatic
Detection Apparatus
-– electrostatic detection
apparatus (ESDA), an
instrument that renders
indented writing visible
and provides a record
of the writing.
CHE 113 38
Typewriters
The typewriter (L) identified with correspondence from
the UNABOM case. Note the unique characteristic of
the typed letter "u" (Middle) from the questioned
document, which matches the unique characteristic of
the "u" typewriter key (R) from the typewriter seized
during the investigation.
CHE 113 39
Altered Documents
Hyperspectral imaging clearly shows the alteration to a
document. (Top) the document as it appears visually and
(bottom) a hyperspectral image showing the use of a
different pen to make the alteration
CHE 113 40
Voice Analysis
Unique voice
production to an
individual is
based on the
physical process
of speech itself…
Speech ProductionThe probability that two people both have
exactly the same physical make-up in their
sound generating structures and employ the
same speech articulations is extremely small.
a method to measure and graphically display the
differences that exist in the subtleties of our
speech, is called a sound spectrograph or
voiceprint.
CHE 113 41
Speech Production– A voiceprint displays three key components of
speech in a single plot
• the vertical axis is used to display the different
frequencies that make up the sound
• the horizontal axis shows time elapsed during the
measurement
• the degree of darkness of the line at a particular
point shows the intensity of that particular frequency
at that one time
CHE 113 42
Basic Concepts for Analyzing
Voice Prints
The process of identifying voices visually
involves translating the wave patterns
produced by the voice into a pictorial
display called a spectrogram.
The spectrogram serves as
a permanent record of the
words spoken and facilitates
the visual comparison of
similar words spoken by an
unknown and known
speaker's voice.
Basic Concepts for Analyzing
Voice PrintsIs it possible for a person to "fool" a spectrograph?