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Published byOswin Allison Modified over 8 years ago
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Aim: How are Documents Analyzed? Do Now: Get a Textbook and Take to Your Seats
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Handwriting and signatures Inks Copy Machines Papers Restoring erased or obliterated writing
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To remove writing by physical or chemical means Erase, scrape, chlorine, etc… Digital Imaging is useful tool used by document examiners to Find Obliterations
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Impressions left on paper beneath the primary writing ◦ Pencil rubbings Electrostatic Detection Apparatus (ESDA) is used to observe indentations ◦ Paper holds “charge” because of static created during rubbing process of criminal ◦ Pour toner over a charges sheet of plastic to see image of impression
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The following characteristics are used to identify paper 1. Color 2. Density 3. Dyes or Bleaches 4. Fluorescence under UV light 5. Thickness 6. Watermarks
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A design incorporated into the paper during manufacturing process by reducing the number of fibers within a certain patterned area
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Investigators compare inks composition (chemical makeup) Can even determine how long ink has been on page A good and inexpensive way to analyze water-based ink is Paper Chromatography
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1. On a separate sheet of paper Sign your name 4 times 2. Place graph paper over signature and mark the top points of each letter Example the letter M has 3 top points 3. Use a ruler to connect the points 4. Repeat for other 3 signatures 5. Now use graph paper to mark the bottom points of each letter 6. Connect points with ruler 7. Note 2 similarities and 2 differences from top analysis 8. Note 2 similarities and 2 differences from bottom analysis
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Using the 4 signature from Activity 16.5 follow the procedure for Activity 16.4 pg. 488 I have 6 letter slant transparency templates to share Answer all questions #1-7 on pg. 488 and hand in
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