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Forensic Science Questioned Documents

Forensic Science Questioned Documents. Documentation. 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

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Forensic Science Questioned Documents

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  1. Forensic ScienceQuestioned Documents Documentation

  2. 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

  3. Comparison Graphologist - attempts to predict character traits from handwriting examination 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.

  4. Handwriting Handwriting analysis involves two phases: • The hardware--ink, paper, pens, pencils, typewriter, printers • Visual examination

  5. 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.

  6. 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??

  7. 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

  8. 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.

  9. Exemplar – Handwriting sample that is the known sample…. the standard

  10. Does asking for your handwriting violate your rights? Answer: Nope 5th Amendment – (the right not to incriminate yourself or testify against yourself)…. The U.S. Supreme Court decided that handwriting is a part of identifying physical characteristics that aren’t protected against ‘the 5th’

  11. And what about that 4th? The U.S. Supreme Court decided that providing a handwriting sample doesn’t violate the 4th Amendment’s protections against unreasonable search and seizure.

  12. Let’s talk about Forgery Forgery – writing or altering a document with intent to defraud Role of forensic examiner: Was the document altered? Role of judge/jury: Was it the writer’s intent to defraud?

  13. 2 Common Ways to Forge • Freehand Simulation 2. Tracing

  14. Common Clues That Give Away Forgery • Underlying tracing • Forger’s tremors (shakiness in the writing) • Uneven writing speed and pen pressure • Hesitations • Unusual pen lifts • Patching and retouching • Blunt beginnings and endings

  15. Disguised Handwriting A deception in which the writer attempts to camouflage his/her handwriting

  16. More Forgery Stuff • Erasures – using an eraser… ultraviolet light, microscope, lycopodium powder • Obliterations – destroy document or obliterate the writing…. Even burned paper can be sprayed, treated with chemicals, even photographed • Alterations – overwriting… like what you guys do on your progress/grade reports… UV light shows 2 different pens easily

  17. Indented Handwriting Created when you write on the top page and it indents the page underneath. So, what would you do to reveal the indented writing? I knew you would say that.

  18. FYI…… Putting pencil over the indented writing tends to destroy the writing. Use angled light, then photograph….. or ESDA – electrostatic detection apparatus

  19. Ink Chromatography – process which physically separate mixtures of gases, liquids or dissolved pigments. Types • Gas Chromatography • HPLC - high-performance liquid chromatography • TLC - thin-layer chromatography • Paper Chromatography

  20. Paper Chromatographywith Ink Two samples of black ink from two different manufacturers run using paper chromatography.

  21. Retention Factor (Rf) • This is a number that represents how far a compound travels in a particular solvent • It is determined by measuring the distance the compound traveled and dividing it by the distance the solvent traveled.

  22. Science Stuff Gas chromatograph - separates mixtures on the basis of their distribution between a stationary liquid phase and a moving gas phase. The written record of the results is called a chromatogram. A typical one will show a series of peaks, with each representing one component of the mixture. The time required to go from the injection out of the column is known as the retention. This allows identification of class characteristics.

  23. Gas Chromatography

  24. More Science Stuff Mass spectrometer - an instrument that connects to the gas chromatograph. The substance to be identified is exposed to a beam of high-energy electrons causing the molecules of the sample to lose electrons and to acquire a positive charge. These positively charged molecules decompose into numerous fragments. These fragments then pass through an electronic or magnetic field where they are separated according to their masses. The unique feature of mass spectrometry is that no two substances produce the same fragmentation pattern, thus producing individual characteristics. In other words… materials are separated into individual components based on mass of molecules.

  25. Paper • Weight • Color • Water marks • Age

  26. 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.

  27. Codes and Ciphers • Codes - letter combinations, numbers or symbols used to represent words or concepts…Morse Code • Interception from terrorists and other war enemies • Ciphers--a message in which letters or symbols replace the actual letters in the message.

  28. 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.

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