Any intervention made on an official or private document in order to change or conceal the truth is defined as “document alteration” (forgery). Alteration may take the form of changing a figure on a promissory note (senet), scribbling over a name, or trying to destroy information with correction fluid.
So does writing that has been blacked out with a pen or covered with correction fluid disappear completely? In forensic document examination the answer is clear: No, it does not.
🔬 Making the Invisible Visible
Scribble over a piece of writing as much as you like: if the chemical composition (carbon content) of the inks differs, our infrared (IR) filtering technology lets us “virtually” remove the overlying scribble and read the original writing beneath it clearly.
NON-DESTRUCTIVE EXAMINATION TECHNIQUES
🔬 NON-DESTRUCTIVE EXAMINATION
⚠️ An Important Distinction: Forensic document examination must not be confused with the approach of an Adana psychologist analysing a person’s character or state of mind from their handwriting. Our work is not about emotions; it is concerned entirely with concrete, physical and chemical findings.
Writing and figures that have been scribbled over with a different pen or covered with a chemical correction fluid can be identified using technical instruments in a laboratory setting, without altering the original state of the document in any way.
Writing and figures that have been scribbled over with a different pen or covered with a chemical correction fluid can be identified using technical instruments, without altering the original state of the document in any way.
Video Spectral Comparator (VSC) instruments used in the laboratory separate the layers of a document using wavelengths of light the human eye cannot see (infrared/IR and ultraviolet/UV). During this examination no chemicals are applied, nothing is scraped off and the document suffers no physical damage.
HOW IS SCRIBBLED-OVER WRITING READ?
When a text is scribbled over with another pen, the original writing underneath and the overlying ink are usually chemically different from each other.
In forensic examination, the “infrared reflectance” and “infrared luminescence” methods come into play. When the document is illuminated at a particular wavelength, the overlying ink becomes transparent to the light while the original writing underneath stays dark and becomes visible. The name, date or figure beneath the scribble can then be read clearly, photographed and recorded as evidence.
DETECTING ERASURES AND SCRAPING
Alteration is not only done by covering writing; sometimes existing writing is erased in an attempt to remove it.
- Mechanical erasure (scraping): Fibres are removed from the paper surface using a razor blade, a knife or a hard eraser. Although the area may look clean to the naked eye, under the microscope it is clear that the paper fibres have been disturbed and that the paper has become thinner in that area.
- Chemical erasure: The ink is removed using thinner, acetone or special chemicals. This leaves a yellowish stain on the paper, and under UV light these stains fluoresce and reveal the forgery.
🛑 Do Not Touch the Document!
Trying to erase or scrape a suspicious area, or shining light on it, can destroy evidence. An alteration examination must only be carried out in a laboratory using non-destructive methods.
DECIPHERING WRITING UNDER CORRECTION FLUID
Correction fluid and correction tape are substances that block light. However, with powerful light sources and filtering techniques it is possible to see behind the correction layer. Using transmitted light and oblique lighting techniques, the original text beneath the correction fluid can be deciphered.
THE TRUTH CANNOT BE HIDDEN
Altering a document constitutes the offence of “forgery of official or private documents” under the Turkish Criminal Code (TCK). Any trace that cannot be seen with the eye, or has been scribbled over or erased, can be brought to light by expert forensic document examiners and well-equipped laboratories. If you doubt the authenticity of a document you hold, or believe the writing on it has been changed, it is vital that you request a professional forensic examination.
DO YOU HAVE A SCRIBBLED-OVER PROMISSORY NOTE?
Get expert support to decipher writing under correction fluid or scribbles.
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