apparatus Material Definition Principles

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Transcript apparatus Material Definition Principles

Apparatuses/ Equipments for QDE
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Stereoscopic microscope
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Hand lens
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Shadowgraph machine
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Compound microscope
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Oblique light
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Micrometer caliper
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Typewriter test plate
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Handwriting portractor
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Ultraviolet lamp
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Transmitted light
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Paper cutter
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Photo enlarger
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Forensic comparator
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Photo paper dryer
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Camera w/ macro lens
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Infra-red image converter
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Video spectral comparator (VSC)
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Forensic optical comparator
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Electrostatic detection apparatus
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EXCELLENT EYESIGHT
Materials that form a document:
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Paper
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Ink
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Writing Instrument
Paper
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Earliest form—parchment or vellum
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papyrus—grass like plant from Egypt
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AD 874—earliest manuscript found from Egypt
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AD 1049—earliest manuscript found in England
Commonly used papers
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Writing paper pad (common paper)
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Carbon paper
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Safety paper
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Treated to minimize chances of forgery by erasure
Bond paper
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Heavily coated with waxy layer which hold sufficient
coloring matter
Commonly used in typewritten documents
Stationaries
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Colored and perfumed, cmmonly used for special letters
Ink
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Earliest ink was in form of vegetable varnish
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Oldest type was invented by the Chinese
Classes of Ink
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Indian ink
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Printing Ink
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Amorphous carbon in the form of lamp-black made
into cake with hide glue
Made by grinding carbon in form of vegetable char
with varnish made of natural gums and drying oils
Canceling Ink
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Often contains carbon; should be checked when
deciphering cancellation marks on postage stamps
or wrappers
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Iron-tannin ink
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Suitable with quill
Record Ink
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Soluble salts of iron mixed with extracts from
vegetable materials such as tan bark and nut galls
used for tannin hide
High quality ink assured of long life
Recommended by Schutting and Neumann in
government specification
Contains 0.5-0.6% iron with minimum concentration
of acid
Fountain pen ink
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Record ink that contains half concentration of iron
compuonds but increased proportion of dye
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Colored ink
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Copying ink
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Contains synthetic dye
Concentrated record ink added with glycerin or
dextrin
Logwood ink
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Formerly widely used but rarely encountered today
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80% dye and remainder is iron-tannin ink
Hectograph ink
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Contains gelatin glycerol mixture of special clay
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Dye is mixed with glucose, glycerol or glycol
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Stamp-pad ink
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Similar to hectograph inks but are heavily loaded
with hhumectants such as glycerol or glycol which
prevents the pad from drying up
May contain solvents such as acetone, methyl
alcohol or ethyl acetate for quick drying
Liquid lead pencil ink
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Ordinary ball point pen with fluid containing finely
divided carbon substituted for dye
Writing Instrument
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Roman beaver
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Reed pen
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Goose quill
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Steel pen
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Fountain pen
Appearance of Document
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Folds and creases
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Impressions
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Cancellation stamps
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Hand stamps of post office
Erasures
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From paper clips or stamp pads
Rubbing the surface of the paper resulting in
reducing thickness of paper
Surface
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Examined in strong sunlight
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Blots and smears
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Devised for obscuring forger's intention to hide
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Result from contact with other writings
Dimensions
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Perforations
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Slight irregularities in tearing
Adhesive stamps
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Forgery may be done by trimming a part of document
rather that attempting to erase
May reveal unsymmetrical outline due to perforations
Holes and tears
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May be deliberately made to cover forgery
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Wire marks and water marks
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Identyfying features of a sheet of paper
introduced into paper at the early stage of
manufacture
Definition of terms
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Document
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Questioned Document
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Any material that contains marks, symbol or signs
that convey message or information
A document which some issues were raised, placed
under scrutiny or of doubtful origin
Questioned Document Examination
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Act of making a close and critical study of document
questioned, disputed, attacked necessary to
discover the facts about them
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Comparison
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Visual and mental act which the element of one
item is related to the counterpart of the other
Collation
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Two or more items are set side by side
(juxtaposition) to weigh their identifying qualities
Ordering or assembling of detailed results of critical
comparison of questioned document
Unified result of detailed comparison between
different items or forms of information
Opinion
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Document examiner's conclusion
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Demonstrate the reason for arriving at the opinion
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Natural variation
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Natural writing
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Normal or usual deviation found between repeated
specimen of any individual handwriting or product of
any typewriter
Specimen of writing executed normally without any
attempt to control or alter its identifying habits and
its usual quality or execution
Forensic document examiner
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Anyone who examines adequate exemplars of
document and provude conclusions, reasons and
photographic demonstrations in court so the court
can make its own determination in giving
appropriate decision
Forensic Document Examiner
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Determine if a questioned document originated
from the same source as the know item
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Present opinion in court as an EXPERT WITNESS
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Determine what happened to a document
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Determine when a document was procured
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Decipher information on a document that has been
obscured, obliterated or erased
Traits of FDE
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Excellent eyesight
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Pass a form blindness test
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Normal color perception
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Bachelor of Science degree
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Training and apprenticeship
Responsibilities of FDE
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Strive constantly to improve professional
standing
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Must be certain of technical conclusion
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Must avoid outside influences
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Must be fair and impartial on the witness stand
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Must protect the innocent
General Principles in QDE
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Documents are questiones, disputed and
attacked on many grounds for various reasons
Documents should be preserved, handled and
cared for in a manner that will not impair the
slightest degree of its value as evidence
QD examination observes phases of specific
approacher