apparatus Material Definition Principles
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Transcript apparatus Material Definition Principles
Apparatuses/ Equipments for QDE
Stereoscopic microscope
Hand lens
Shadowgraph machine
Compound microscope
Oblique light
Micrometer caliper
Typewriter test plate
Handwriting portractor
Ultraviolet lamp
Transmitted light
Paper cutter
Photo enlarger
Forensic comparator
Photo paper dryer
Camera w/ macro lens
Infra-red image converter
Video spectral comparator (VSC)
Forensic optical comparator
Electrostatic detection apparatus
EXCELLENT EYESIGHT
Materials that form a document:
Paper
Ink
Writing Instrument
Paper
Earliest form—parchment or vellum
papyrus—grass like plant from Egypt
AD 874—earliest manuscript found from Egypt
AD 1049—earliest manuscript found in England
Commonly used papers
Writing paper pad (common paper)
Carbon paper
Safety paper
Treated to minimize chances of forgery by erasure
Bond paper
Heavily coated with waxy layer which hold sufficient
coloring matter
Commonly used in typewritten documents
Stationaries
Colored and perfumed, cmmonly used for special letters
Ink
Earliest ink was in form of vegetable varnish
Oldest type was invented by the Chinese
Classes of Ink
Indian ink
Printing Ink
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
Often contains carbon; should be checked when
deciphering cancellation marks on postage stamps
or wrappers
Iron-tannin ink
Suitable with quill
Record Ink
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
Record ink that contains half concentration of iron
compuonds but increased proportion of dye
Colored ink
Copying ink
Contains synthetic dye
Concentrated record ink added with glycerin or
dextrin
Logwood ink
Formerly widely used but rarely encountered today
80% dye and remainder is iron-tannin ink
Hectograph ink
Contains gelatin glycerol mixture of special clay
Dye is mixed with glucose, glycerol or glycol
Stamp-pad ink
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
Ordinary ball point pen with fluid containing finely
divided carbon substituted for dye
Writing Instrument
Roman beaver
Reed pen
Goose quill
Steel pen
Fountain pen
Appearance of Document
Folds and creases
Impressions
Cancellation stamps
Hand stamps of post office
Erasures
From paper clips or stamp pads
Rubbing the surface of the paper resulting in
reducing thickness of paper
Surface
Examined in strong sunlight
Blots and smears
Devised for obscuring forger's intention to hide
Result from contact with other writings
Dimensions
Perforations
Slight irregularities in tearing
Adhesive stamps
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
May be deliberately made to cover forgery
Wire marks and water marks
Identyfying features of a sheet of paper
introduced into paper at the early stage of
manufacture
Definition of terms
Document
Questioned Document
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
Act of making a close and critical study of document
questioned, disputed, attacked necessary to
discover the facts about them
Comparison
Visual and mental act which the element of one
item is related to the counterpart of the other
Collation
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
Document examiner's conclusion
Demonstrate the reason for arriving at the opinion
Natural variation
Natural writing
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
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
Determine if a questioned document originated
from the same source as the know item
Present opinion in court as an EXPERT WITNESS
Determine what happened to a document
Determine when a document was procured
Decipher information on a document that has been
obscured, obliterated or erased
Traits of FDE
Excellent eyesight
Pass a form blindness test
Normal color perception
Bachelor of Science degree
Training and apprenticeship
Responsibilities of FDE
Strive constantly to improve professional
standing
Must be certain of technical conclusion
Must avoid outside influences
Must be fair and impartial on the witness stand
Must protect the innocent
General Principles in QDE
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