Alternation,+Obliteration,+and+Ink+Exmaination

Alternation, Obliteration, and Ink Examination
 * Examinations may seem to be straightforward, but there may be a trail of deception that may lead to the undoing of the suspect
 * Secondary lines, erasing, and subtle differences in changing can all be overlooked easily but are key to the identification
 * Light Spectrum
 * Video Spectrum Comparison (VSC)
 * infared imaging equiptment
 * the human eye observes a rainbow of colors, but it cannot observe ultraviolet (UV) or infrared (IR) areas
 * for these other wavelengths, we use instruments to observe
 * Under these circumstances, ink may behave differently such as glowing, disappearing, or appearing unchanged
 * Thin Layer Chromotology (TLC)
 * used for ink comparisons
 * punches of ink are taken with a blunted hypodermic needle- does little damage to the document (microscopic)
 * the ink is put into alcohol and covered. as it rises, it will stop at certain areas, forming certain lines, identifying the type of ink
 * Ink Line Striae
 * miscroscopic methods used to identify ballpoint pens
 * Indented Writing
 * (Second Page Writing)- the impression from the writing insturment
 * often found on pads of paper
 * recovered photographically
 * oblique or glancing light to furrows of indented writing
 * multiple exposures reproduces indented writing
 * recovered electrostatic detection apparatus (ESDA)
 * electrostatic charge