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Questioned Documents
Questioned Documents
• Definition:– Any document about which some issue has been
raised or that is the subject of an investigation• Questioned Document Examination– The part of forensic science pertaining to documents.
• Types of Documents– Sheet of paper, ransom note, forged check, contracts,
graffiti, impressions, labels, emails, photos,IDs, etc– Handwriting, signature, or mark
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Types of Examination–Handwriting analysis–Ink (and pens)–Paper (and pencils)–Forgery–Codes and Ciphers
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Terms to Know
• Erasure: erasing part of a document• Indented writing: found on the second page
where writing from the top indented the words into the second
• Uniqueness: makes handwriting a type of physical evidence like fingerprints; has individual characteristics
• Exemplar: sample of known handwriting, print, etc.
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Who Examines them?• Graphologist: attempts to predict character traits
from handwriting examination
• Forensic Document examiner: involves the analysis & comparison of questioned documents with known material in order to identify the author or origin of the questioned document
• Linguist: Examines the language, punctuation used to determine education level, etc.
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What’s Involved in handwriting analysis?
• Involves two phases:• The hardware: ink, paper,pen, pencils,
typewriter, printers, etc.• 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—dotted I’s, crossed t’s• Baseline Habits• Body Placement
Ransom Note Activity
• Can you determine who wrote the ransom note?
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How is Handwriting Identification done?
• “ACE”– Analysis of the “knowns” – Analysis of the questioned or unknown writing – 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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How should Handwriting Samples be handled?
• 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 (paper, pen)
• The dictated text should match some parts of the document
• The subject should be asked to sign the text• Always have a witness
Can you Forge a Signature?
Blank Piece of Paper
1. Write your Signature 5 times.2. Now try to write your signature EXACTLY as
you did in the 5th sample.3. Ask your partner to write your signature
EXACTLY as you did in the 5th sample.4. Complete the handout.
Disguised Writing
Suspects will often try to disguise their writing.• Inconsistent slant and formation• Slowly written• Major changes from letter to letter• Often use block lettering• Often write with the wrong hand• Excessive ornamentation
Can you Successfully Disguise your writing??
• Write this sentence normally:– I am in possession of the secret formula for Super
Cola.• Write the sentence again, trying to make it
look different, but at a normal rate of speed• Write the sentence a third time, with you
other hand.• Complete the handout.
Handwriting Analysis Activities
• Top-of-the Letter• Bottom-of-Letter• Spacing• Slant
• Even writing that looks different will have the same results with these analyses.
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How can typewriting be identified?
• The type can help determine the make and model of typewriters
• Compare to class standards for each machine• Must be a visual comparison• Serial numbers can identify particular
machines• Type face sizes
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How are photocopiers, printers and fax machines analyzed?
• Look for defect marks: glass paten, inner cover or mechanical portion of copiers produce images and may have damage
• TTI: transmitting terminal identifier that is at the top of each fax page is important point of comparison; analyze number of characters, their style, and position in the header
• Printer types: impact(thermal & dot-matrix)• nonimpact (ink jet & laser printer)
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What are some class characteristics for these?
• Type of paper• Type of toner or ink• Chemical composition of the toner• Type of toner to paper fusing method
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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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How is ink analyzed?Chromatography--physically separate mixtures of gases,
liquids or dissolved.Types– Gas Chromatography– HPLC--high-performance liquid chromatography– TLC--thin-layer chromatography – Paper Chromatography
Ink Catalogs: US Treasury Dept. has a systematic catalog of inks according to their dye patterns using TLC
Tagging: programs that slightly changes the ink year by year for identification purposes
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Paper Chromatographywith Ink
Two samples of black ink from two different manufacturers run using paper chromatography.
Ink is added on line Solvent moves up the paper
carrying the ink molecules with it
Paper Chromatography Lab
Techniques for Uncovering Alterations, Obliterations, Variations
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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.