Questioned Documents. Forensic Science

Transcription

1 Questioned Documents Forensic Science

2 Type Script Comparison and Altered Documents

3 Typescript Comparisons Typescript is the result of machine-created documents, such as computer printers, photocopiers, fax machines, and typewriters Defects, missing pieces, or scratches may help to identify the machine where the document originated 3

4 Typescript Comparisons (continued) Computer printers the kind of ink and toner (inkjet vs. laser printer) Photocopiers the debris patterns Fax machines have a Transmitting Terminal Identifier (TTI) Typewriters Characteristics of the typeface, characters, and the ribbon The Haas Atlas is a typewriter catalog 4

5 Technology Used in Handwriting Analysis Biometric Signature Pads This computerized pad learns to recognize how a person signs his or her name based on the speed, pressure, and rhythm of the signing. Forgeries then are recognized by the detection of even slight differences. Computerized Analysis of Handwriting Computers can make objective comparisons between handwritings. Suspect signatures can be compared with ones stored in databases. 5

6 Handwriting Evidence in the Courtroom The expert shows how comparisons were made. The defense attorney likely will cross-examine the handwriting expert. Shortcomings in Analysis A particular piece of handwriting can be different from its usual style because of factors such as fatigue. Experts can miss details. 6

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8 Altered Documents Documents are often altered after they have been prepared. This is sometimes done to hide the original content or commit a forgery Additions : Adding content to an already prepared document Infrared luminescence can reveal if a different ink than the original was used, as it may emit infrared light when exposed to blue green light. 8

9 Altered Documents (continued) Erasures One of the most common alterations An India rubber eraser, sandpaper, razor blade, or knife may be scratched against the paper s surface in an attempt to remove writing or type This irritates the top fibers of the paper which are visible under a microscope 9

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11 Altered Documents (continued) Obliterations A document may have parts blotted, smeared, or covered over making the original unreadable This is sometimes done with strong oxidizing agents to make the ink become colorless This is not always visible to the naked eye, but can be seen with microscopes, or ultraviolet or infrared lighting 11

12 Altered Documents (continued) Charred Documents Sometimes documents are accidently or purposely charred in a fire Infrared photography or reflecting light at different angles can sometimes reveal the document s contents 12

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14 Other Document Challenges Indentations Most of the time an indented impression is left on a paper below the primary writing The best way to read the impression is by using an ESDA (Electrostatic Detection Apparatus) This charges the paper Pouring toner powder over the charged paper develops the images on the indented paper 14

15 Other Document Challenges (continued) Paper To identify paper, scientists may use the following characteristics Color Density Watermarks Dyes or bleaches Fluorescence under UV light Raw material the paper is made from Thickness 15

16 Other Document Challenges (continued) Ink Thin Layer Chromatography (TLC) can break down the ink mixture to reveal the components A microspectrophotometer can use light to indentify chemical components Studying the chemical composition can help determine If a certain pen was used on a questioned document How long the ink has been on the paper Thin Layer Chromatography (TLC) Microspectrophotometer

17 Other Document Challenges (continued) Physical/Fracture Match of separated documents usually these documents are cut or torn and can be linked to the original source 17

18 Forgery

19 Forgery An item prepared with the intent to deceive Blind forgery made without a model of the signature or the writing being forged Simulated forgery made by copying a genuine signature Traced forgery one made by tracing a genuine signature Martin Coneely was arrested in 1937 for selling a forged Abraham Lincoln letter. Ironically, his forgeries are valuable collector s items today. 19

20 A sample of a forged doctors? note, not all forgeries are for material gain (fraudulence). 20

21 Fraudulence Case Study: M. Coneely Martin Coneely was a fraudulent forger of Abraham Lincoln s signature in the early 1900 s. Ultimately he was arrested and spent time in prison. His forgeries are collector s items today. 21

22 Fraudulence Case Study: M. Coneely Coneely s forgery is on top. Lincoln s signature is below. Using your handwriting analysis skills identify characteristics that separate these two signatures. 22

23 Check Forgery and Fraudulence Americans write 70 billion checks each year. $27 million in illegitimate checks are cashed each! DAY 23

24 Check Forgery As much as $27 million in illegitimate checks are cashed each day worldwide. Criminals can get these checks by: Ordering someone else s checks from a deposit slip (at the end of a check book) Altering a check Creating forged checks from scratch

25 Check Forgery Frank Abignale Jr. Famous con-man, imposter, and check forger In the 1960 s he created many near-perfect checks He now works for the federal government as a consultant to the FBI, and runs his own anti-fraud advisory firm His life story was the basis for the 2002 film, Catch Me If You Can

26 Check Forgery and Fraudulence Criminals can alter or acquire checks in several ways Ordering someone else s checks from a deposit slip Directly altering a check Intercepting someone s check, altering it, and cashing it Creating forged checks from scratch 26

27 Original Check Washed Check 27

28 Check Forgery Methods to prevent check forgery Print checks on chemically sensitive paper Use a larger font size that requires more ink and makes alterations more difficult Create high resolution borders that are difficult to copy Print checks in multiple color patterns Embed fibers in checks that glow under different types of light Use chemical wash detection systems that change color when a check is altered

29 Literary Forgery Forgery of a piece of writing, such as a historic letter or manuscript Forgers try to duplicate the original materials like paper and ink. Can you think of ways that they could do this? Using old books for paper Mixing their own inks Chemically aging paper and ink 29