1. Computer Analysis

2. Linguist
Language that is used can help to establish the writer’s age, gender, ethnicity, level of education, professional training, and ideology.

3. Typescript Comparisons
There are several mechanical devices and machines a document examiner encounters
Computers
Typewriters
Typewriter ribbon
Photocopiers
Printers
Fax machines

4. Document Alterations
Obliterations—removal of writing by physical or chemical means can be detected by:
Microscopic examination
UV or infrared (IR) light
Digital image processing
Indentations can be detected by:
Oblique lighting
Electrostatic detection apparatus (ESDA)

5. Alterations, Erasures, and Obliterations
The most common way to alter a document is erasure, either using an Indian rubber erasure, or with chemicals.
These changes can be seen under a microscope using direct or side lighting.

6. Alterations, Erasures, and Obliterations
Examiners often use Infrared Luminescence.
When some inks are exposed to blue-green light, they absorb the radiation and reradiate infrared light, making any alterations visible with infrared sensitive
film.
Infrared luminescence
can also reveal writing
that has been erased.

7. Infrared Luminescence examples

8. Alterations, Erasures, and Obliterations
Obliteration is the act of blotting or smearing over a writing or printing to make the original unreadable.
The contents of a charred
document can sometimes
Be revealed through infrared
photography.

9. Other Document Evidence
Indented writings are the impressions
left on papers positioned under a
piece of paper that has been written on.
Sometimes the document is readable
with oblique lighting,
or angling the
document against
the light.

10. Other Document Problems
Electrostatic charge can be
applied to the surface if the
indented document, then
layered with toner powder to
produce an image.

11. Ink
Chromatography--physically separates mixtures of gases, liquids or dissolved solids.
Types
Gas Chromatography
HPLC--high-performance liquid chromatography
TLC--thin-layer chromatography
Paper Chromatography

13. Specialized Ligthing

14. Paper Differences Raw material Weight Density Thickness Color
Watermarks
Age
Fluorescence
True Watermark
Forged Watermark

15. Other Document Problems
Paper examined under a microscope can reveal:
Fibers Fillers
Pigments Additives
Non-coated Coated

16. Evidence
Class characteristics may include general types of pens, pencils or paper.
Individual characteristics may include unique, individual handwriting characteristics; trash marks from copiers, or printer serial numbers.

17. CRAZY CRIMINALS
According to Point of View, a magazine published by the Alameda county District Attorney’s office, a guy walked into an Oakland bank and handed the teller a note reading, “this is a stikkup. Hand over all yer money fast.”
Guessing from this that the guy was no rocket scientist, the teller replied, “I’ll hand over the cash as long as you sign for it. It’s a bank policy that all robbers have to sign for their money.”
The guy thought this over, then said “Uh, I guess that’s OK.” He signed his full name and address. That’s where the cops found him a few hours later.

18. More about Document Analysis
For additional information about document and handwriting analysis, check out Court TV’s Crime Library at:
lwww.crimelibrary.com/criminal_mind/forensics/literary/1.htm
Or forgery cases at: