Forensic Science Documentation

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Forensic Science
Questioned Documents
Documentation
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Questioned Documents
Involves the examination of handwriting, ink,
paper, etc. to ascertain the source or
authenticity
Examples include letters, checks, licenses,
contracts, wills, passports, etc.
Topics
Handwriting analysis
Ink (and pens)
Paper (and pencils)
Forgery
Codes and Ciphers
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COMPARISON
Graphologist--attempts to
predict character traits
from handwriting
examination
The lower-case "t" in Bundy's signature "indicates a very low
opinion of himself, usually caused by significant damage to the
ego early in life" -- according to document examiner Brown.
Forensic Document Examiner-involves the analysis and
comparison of questioned
documents with known
material in order to identify
whenever possible, the
author or origin of the
questioned document.
Unfortunately, no federal
licensing exists. There is
certification through the
ABFDE.
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Handwriting
Handwriting analysis involves two phases:
The hardware--ink, paper, pens, pencils,
typewriter, printers
Visual examination
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Handwriting Characteristics
Line Quality
Word and Letter Spacing
Letter Comparison
Pen Lifts
Pen Pressure
Lettering Slant
Unusual Letter Formation
Diacritic Placement
Baseline Habits
Body Placement
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Handwriting Identification
“ACE”
Analysis of the “knowns” with a determination of the
characteristics found in the known
Analysis of the questioned or unknown writing and
determination of its characteristics
Comparison of the questioned writing with the known
writing.
Evaluation of the evidence, including the similarities and
dissimilarities between the “questioned” and “known” writing.
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Handwriting Analysis
Handwriting Sample of President
George Bush
According to Sheila Lowe in her book,
Handwriting of the Famous and
Infamous, President Bush’s
handwriting is “fast and highly
simplified in fairly well-organized
writing field”.
Is this a forensic document examiner or
a graphologist??
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Handwriting Samples
The subject should not be shown the questioned
document
The subject is not told how to spell words or use
punctuation
The subject should use materials similar to those of the
document
The dictated text should match some parts of the
document
The subject should be asked to sign the text
Always have a witness
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Linguist
Experts that look at the linguistic content (the
way something is written) of a questioned
document.
Language that is used can help to establish the
writer’s age, gender, ethnicity, level of
education, professional training, and
ideology.
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Ink
Chromatography--physically separate mixtures
of gases, liquids or dissolved.
Types
Gas Chromatography
HPLC--high-performance liquid chromatography
TLC--thin-layer chromatography
Paper Chromatography
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Paper Chromatography
with Ink
Two samples of black ink
from two different
manufacturers run using
paper chromatography.
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Retention Factor (Rf)
This is a number that
represents how far a
compound travels in a
particular solvent
Rf = distance solute travels
distance of solvent front
Scientific Equipment
 Gas chromatograph--used to
separate mixtures on the basis
of their distribution between a
stationary liquid phase and a
moving gas phase.
 Chromatogram-the written
record of the results is called a
chromatogram.
 Peaks
 Time tracked on x axis--this is
known as retention time.
 Example: amounts of “hot”
compounds in a particular
pepper pod.
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Scientific Equipment
con’t
Mass spectrometer--an
instrument that connects to the
gas chromatograph.
 The substance to be identified
is exposed to a beam of highenergy electrons causing the
molecules to decompose into
numerous fragments.
 These fragments then pass
through field where they are
separated according to their
masses.
 No two substances produce
the same fragmentation
pattern, thus producing
individual characteristics.
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Paper Characteristics
Weight
Color
Water marks
Age
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Pencils
Lead
Hardness Scale--a traditional measure of the
hardness of the "leads" (actually made of graphite) in
pencils. The hardness scale, from softer to harder,
takes the form ..., 3B, 2B, B, HB, F, H, 2H, 3H, 4H,
..., with the standard "number 2" pencil being of
hardness 2H.
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Forgery
Check Fraud
Forgery
Counterfeit
Alterations
Paper Money
Counterfeit
Identity
Credit Cards
Theft of card or number
Art--imitation with intent to
deceive
Microscopic examination
Electromagnetic radiation
Chemical analysis
Social Security
Driver’s license
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Codes and Ciphers
Codes--letter combinations or symbols
used to represent words or concepts
Interception from terrorists and other war
enemies
Ciphers--a message in which letters or
symbols replace the actual letters in the
message.
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Used as Evidence
1. Class characteristic--the type of ink may have
similar characteristics at the primary and/or
secondary crime scene, on the suspect or on the
victim. Handwriting may be used to include or
exclude a suspect.
2. Individual characteristic--With document analysis,
it is difficult to identify to an individual
characteristic except with typewriter or printer
specific marks.
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CRAZY CRIMINALS
According to Point of View, a magazine
published by the Alameda county District
Attorney’s office, a guy walked into an
Oakland bank and handed the teller a note
reading, “this is a stikkup. Hand over all yer
money fast.”
Guessing from this that the guy was no rocket
scientist, the teller replied, “I’ll hand over the
cash as long as you sign for it. It’s a bank
policy that all robbers have to sign for their
money.”
The guy thought this over, then said “Uh, I
guess that’s OK.” He signed his full name
and address. That’s where the cops found
him a few hours later.
You are to do “Fraud and Counterfeiting as
homework. It is DUE: November 13th.
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 You will be given a black ink pen.
 Each of you will write the same message.
 Give the teacher your handwriting sample when you are finished.
 Sign your name on the bottom in pencil.
Write the following:
I have your daughter. Do what you are told and no one will
get hurt. Put 100,000 dollars worth of 20’s in a suitcase
and place it in locker number C8160 at the bus depot. I
will get back in touch with you aas to the whereabouts of
your daughter.
Your loyal fan.
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