Policie České republiky – Kriminalistický ústav
7
Zkoumání ručního písma
Handwriting examination
Example of technical forgery
If an expert discovers two completely identical signatures during the examination, he can state with 100% certainty that at least one must be a technical forgery (for example, a signature covered according to some pattern in the translucence). Creating a so-called technical forgery is not that difficult. It is enough to compare both signatures using the superprojection setting, when both signatures overlap. The almost absolute accuracy of the stroke proves that it is a forged signature (obtained according to the pattern).
- Questionned signature No. 1
- Questionned signature No. 2 – a copy
- Superprojection
Examination of the wrriting strokes sequence
Experts from the field of handwriting examination, in cooperation with colleagues from the field of technical examination of documents and writings, also deal with deciphering illegible, transcribed or overprinted texts and identifying the writer of these texts.
- Questionned signature No. 1
- Questionned signature No. 2 – a copy
Filtered writing paste of questionned signature. Is is apparent, that a pen pressure occurs in places where the writing paste is omitted, which did not interrupt the stroke.
- Signature analysis
A case of signature analysis
An expert evaluates, for example, slope, length, height and fluency of characters, character height and width ratios, initial and final adjustment, layout, spacing etc.
How to prevent signature forgery?
- the signature should be graphically simple (a simple signature is easily imitated),
- the signature should not be written in block letters,
- the more and graphically complex a signature is, the harder is to imitate,
- the signature may include various signs,decorative initials, return and counterstrokes, which makes it difficult for the perpetrators to create a succesfull forgery .