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Soil and Glass Analysis

Soil and Glass Analysis. Objectives, continued. You will understand: The difference between physical and chemical properties. How glass can be used as evidence. How individual evidence differs from class evidence. The nature of glass.

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Soil and Glass Analysis

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  1. Soil and Glass Analysis

  2. Objectives, continued You will understand: The difference between physical and chemical properties. How glass can be used as evidence. How individual evidence differs from class evidence. The nature of glass. How to use the properties of reflection, refraction, and refractive index to classify glass fragments.

  3. Hard, amorphous solid Usually transparent Primarily composed of silica, with various amounts of elemental oxides Brittle Exhibits conchoidal fracture Characteristics of Glass

  4. Soda-lime—used in plate and window glass, glass containers, and electric lightbulbs Soda-lead—fine tableware and art objects Borosilicate—heat-resistant, like Pyrex Silica—used in chemical ware Tempered—used in side windows of cars Laminated—used in the windshield of most cars Common Types

  5. Density—mass divided by volume Refractive index (RI)—the measure of light bending due to a change in velocity when traveling from one medium to another Fractures Color Thickness Fluorescence Markings—striations, dimples, etc. Physical Characteristics

  6. Density

  7. Radial fracture lines radiate out from the origin of the impact; they begin on the opposite side of the force. Concentric fracture lines are circular lines around the point of impact; they begin on the same side as the force. 3R rule—Radial cracks form a right angle on the reverse side of the force. Fracture Patterns

  8. A high-velocity projectile always leaves a wider hole at the exit side of the glass. Cracks terminate at intersections with others. This can be used to determine the order in which the fractures occurred. Sequencing

  9. Class characteristics: physical and chemical properties such as refractive index, density, color, chemical composition Individual characteristics: if the fragments can fit together like pieces of a puzzle, the source can be considered unique Glass as Evidence

  10. Document and Handwriting Analysis Kendall/Hunt Publishing Company

  11. Objectives You will understand: That an expert analyst can individualize handwriting to a particular person. What types of evidence are submitted to the document analyst. Three types of forgery. How to characterize different types of paper. The types and impact of computer crime.

  12. Objectives, continued You will be able to: Analyze handwriting using 12 points of analysis. Detect deliberately disguised handwriting. Detect erasures and develop impression writing. Design an experiment using paper chromatography to determine which pen altered a note. List safeguards against the counterfeiting of U.S. currency. Recognize some of the methods of internet fraud.

  13. Involves the examination of handwriting, ink, paper, etc., to ascertain source or authenticity Examples include letters, checks, licenses, contracts, wills, passports Investigations include verification; authentication; characterizing papers, pigments, and inks Questioned Documents

  14. Historical dating—the verification of age and value of a document or object Fraud investigation—focuses on the money trail and criminal intent Paper and ink specialists—date, type, source, and/or catalog various types of paper, watermarks, ink, printing/copy/fax machines, computer cartridges Forgery specialists—analyze altered, obliterated, changed, or doctored documents and photos Typewriting analysts—determine origin, make, and model Computer crime investigators—investigate cybercrime Related Fields

  15. Forensic document examination 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. Document Examination

  16. Handwriting analysis involves two phases: The hardware—ink, paper, pens, pencils, typewriter, printers Visual examination of the writing Handwriting

  17. Line quality Word and letter spacing Letter comparison Pen lifts Connecting strokes Beginning and ending strokes Unusual letter formation Shading or pen pressure Slant Baseline habits Flourishes or embellishments Diacritic placement Handwriting Characteristics

  18. Analysis of the known writing 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 The document examiner must have enough exemplars to make a determination of whether or not the two samples match. Handwriting Identification

  19. 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. Handwriting Samples

  20. Simulated forgery—one made by copying a genuine signature Traced forgery—one made by tracing a genuine signature Blind forgery—one made without a model of the signature Methods of Forgery

  21. Check fraud Forgery Counterfeit Alterations Paper money Counterfeit Identity Social Security Driver’s license Credit cards Theft of card or number Art—imitation with intent to deceive Microscopic examination Electromagnetic radiation Chemical analysis Contracts—alterations of contracts, medical records Types of Forgery

  22. Obliterations—removal of writing by physical or chemical means can be detected by: Microscopic examination UV or infrared (IR) light Digital image processing Indentations can be detected by: Oblique lighting Electrostatic detection apparatus (ESDA) Document Alterations

  23. Major George Byron (Lord Byron forgeries) Thomas Chatterton (literary forgeries) John Payne Collier (printed forgeries) Dorman David (Texas Declaration of Independence) Mark Hofmann (Mormon, Freemason forgeries) William Henry Ireland (Shakespeare forgeries) Clifford Irving (Howard Hughes forgery) Konrad Kujau (Hitler diaries) James Macpherson (Ossian manuscript) George Psalmanasar (literary forgery) Alexander Howland Smith (historical documents) Famous Forgers and Forgeries

  24. Expert who looks 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. Forensic Linguist

  25. Chromatography is a method of physically separating the components of inks. Types HPLC—high-performance liquid chromatography TLC—thin-layer chromatography Paper chromatography Ink

  26. Paper Chromatography of Ink Two samples of black ink from two different manufacturers have been characterized using paper chromatography.

  27. Document and Handwriting analysis Retention Factor (Rf) 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. 18

  28. Differences Raw material Weight Density Thickness Color Watermarks Age Fluorescence Paper

  29. 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. Pencils

  30. Class characteristics may include general types of pens, pencils, or paper. Individual characteristics may include unique, individual handwriting characteristics; trash marks from copiers; or printer serial numbers. Evidence

  31. Counterfeiting In 1996 the government starting adding new security features to our paper money due to the advanced copying technologies that have raised the incidence of counterfeiting. The $20 bill entered circulation on October of 2003, followed by the $50 in September of 2004, and then the $10 in September of 2005. Subtle background colors have been added along with other features to discourage counterfeiting.

  32. Internet Crimes Computer intrusions Identity theft Transmission of illegal items Extortion and harassment Piracy Cyberterrorism

  33. For additional information about document and handwriting analysis, check out truTV’s Crime Library at: www.crimelibrary.com/criminal_mind/forensics/literary/1.htm Or learn about forgery cases at: www.crimelibrary.com/criminal_mind/scams/lincoln_forgers/index.html More about Document Analysis

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