lecture 17: questioned documents

what is a questioned document?

• any document about which some issue has been raised or that is the subject of an investigation

• letters, checks, driver’s licenses, contracts, wills, voter registrations, passports, petitions, lottery tickets

• may include writings or other markings found on walls, windows, doors, or any other objects

handwriting comparisons

• no two individuals write exactly the same

• examiners look at:

  • general style

  • variations in handwriting

  • arrangement of writing on paper

  • spelling, punctuation, grammar

There are two main writing systems taught in the U.S.

• palmer method

• saner-bloser method

variations in handwriting

• individual variations associated with mechanical, physical, and mental functions make it extremely unlikely that all of these factors can be exactly reproduced by any two people

• variations are expected in angularity, slope, speed, pressure, letter and word spacings, pen movement, writing skill, and finger dexterity

challenges of handwriting comparison

• if the examiner has enough known handwriting for comparison to questioned sample. it is usually not difficult to determine if they come from the same soure

• this is usually not the case

  • unable to obtain enough known handwriting samples

• sometimes the questioned document only contains a few words, and there may have been attempts to disguise the handwriting

handwriting examples

• exemplar: an authentic sample used for comparison purposes

• known writings of the suspect furnished to the examiner should be as similar as possible to the questioned document: writing implement and paper

• natural variations; normal deviations found between repeated specimens of an individual’s handrwiting or any printing device

forged signatures

• a signature forged by tracing an authentic signature can often be detected even if original and tracing coincide exactly because no one ever signs two signatures exactly alike

obtaining writing samples

• requested writing sample may be altered by writer: several pages of writing, writing dictation

  1. the writer should be allowed to write sitting comfortably at a desk or table and without distraction

  2. the suspect should not under any conditions be shown the questioned document or be told how to spell certain words or what punctuation to use.

  3. the suspect should be furnished a pen and paper similar to those used in the questioned document

  4. the dictated text should be the same as the contents of the questioned document, or at least should contain many of the same words, phrases, and letter combinations found in the document. In handprinting cases, the suspect must not be told whether to use uppercase or lowercase lettering. If after writing several pages the writer fails to use the desired type of lettering, he or she can then be instructed to include it. Altogether the text must be no shorter. than a page

  5. dictation of the text should take place at least three times, if the writer is trying to disguise the writing, noticeable variations should appear among the three repetitions. discovering this the investigator must insist on continued dictation through text.

  6. signature exemplars can be best obtained when the suspect is required to combine other writings with a signature. for example, instead of compiling a set of signatures alone, the writer might be asked to fill out completely 20-30 separate checks or receipts, each of which includes a signature.

  7. before requested exemplars are taken from the suspect, a document examiner should be consulted and shown the questioned specimens

typescript comparisons

• photocopiers, faxes, printers

• need to determine make, model

• may need to compare questioned document with test sample printed from suspect machine

printers

• need to identify printing technology, type of paper, type of ink, chemical composition of toner

• character shapes, toner differentiation, and toner application methods are easily determined with a low-power microscope

• examination of the toner usually involves microscopic analysis to characterize its surface morphology, followed by identification of the inorganic and organic components of the toner

types of printers

• impact printers: thermal and dot-matrix

• Non-impact: inkjet and laser

photocopiers

• transitory defect marks originating from random debris on the glass paten, inner cover, or mechanical portions of a copier produce images

• images are often irregularly shaped and sometimes form distinctive patterns

fax machines

• same approach as copiers

• fax machines print a header known as a transmitting terminal identifier (TTI)

erasures and alterations

perpetrator may use chemical instead of or in addition to erasing examination under microscope or using UV or IR light can reveal chemical alterations. Inks may also differ in how they absorb infrared light

obliterations

• obliteration: the blotting out or smearing over of writing or printing to make the original unreadable

• if it is done with the same ink as was used to write the original material, recovery will be difficult if not impossible

charred documents

• examiner will reflect light off the paper’s surface at different angles in order to contrast the writing against charred background

indented writings

method involves applying an electrostatic charge to the surface of a polymer film that has been placed in contact with a questioned document. indented impressions on the document are revealed by applying a toner powder to the charged film

Ink and paper comparison

• non-descriptive method for comparing ink uses a visible-light microspectrophotometer

• can also use TLC for ink comparison

• the most common features associated with a paper examination are general appearance, color, weight, and watermarks