3. Silver nitrate method: The method was discovered by Superintendent Cherrill of Scotland Yard. Cherrill places the hot paper on a glass plate resting on the lowest edge of a regular photo editing pan. A 5% aqueous silver nitrate solution is poured over the fragment and a second glass plate is then placed on the fragment. The fragment must be protected from sunlight and within three hours the font is developed as a black image on the gray background of the paper. In the stabilization part, the documents are placed in polyvinyl acetate to obtain a better result in the decryption step. Charred documents are also part of the documents declared in FSLs. Another theory also suggests soaking the packets in alcohol, breaking the link between the fragments and thus separating the documents. Decryption is the process of decrypting the text or writing or a written language in the documents in question. 2. Alcoholic glycerin immersion method: Black developed this method based on the phenomenon in which differences in reflection values between different parts of carbonization can be amplified by immersion in certain liquids.
The components of the alcohol-glycerin solution are 2 parts water, 5 parts alcohol and 3 parts glycerin, in which the documents are immersed for different periods. Careful handling is required to ensure that the charred document remains intact during transport from the crime scene to the forensic laboratory in order to decipher the written contents and analyze the authenticity of the document. The above information on the forensic examination of fire and water damage has been carefully studied and noted. 66. In handwriting, a short opening or closing stroke is mentioned: in infrared photography, light from water-damaged documents is transmitted through the blue-green infrared blocking filter, through which residual ink in the paper shows fluorescence in the infrared. Recorded fluorescence can be used to decipher the writing. Careful handling of the charred document involves placing the document between layers of loose cloth or cotton, and no attempt is made to fold or unfold the charred document. Charred documents, if handled by experts with extreme care and appropriate methods, can be put in a legible form. A document that has become blackened and brittle due to burning or excessive heat exposure may be called a charred document. Documents accidentally burned or intentionally destroyed are taken to forensic laboratories for restoration and decryption of writings.
Because burned documents are extremely fragile, they usually do not remain in their original form and are broken into small fragments. Curling is determined around the edges of the document. Therefore, it is necessary to exercise the utmost care in the handling, storage and transport of documents to forensic laboratories. 70. The serial number stamped on the barrel may be replaced by · Do not point fans directly at water-damaged documents They will be reported to the forensic laboratory for the purpose of restoring and deciphering the handwriting. During the combustion process, the handwriting can be seen on the paper and must therefore be photographed immediately. Once the charred documents have been brought to forensic laboratories, they must be examined using various techniques such as photographic or visual methods. Before decrypting charred documents, the following steps play a crucial role in decrypting documents. The steps are as follows: 37. Writing on a charred document can be retrieved by: 59. Signatures affixed to cheques, driver`s licenses and other official documents are examples of: Documents soaked in water and found near or on the bodies of an unidentified person in a state of decomposition or recovered from the mouth of the suspect who attempted to destroy them by eating or swallowing.
In the above cases, the effect of moisture can cause the paper to adhere to itself in a screwed mass or to mate individual pages. Ink can also leak due to water penetration. The pages of the wet document should be carefully separated from each other so as not to destroy the evidence. Freeze-drying is an effective separation method. In freeze-drying, the dried mass of the documents is soaked in water and then placed in the freeze-drying chamber so that the water is removed. When the water is removed, the substance that holds the paper together is broken down and the paper separates. 3. Infrared photography: This is one of the most widely published decryption methods. This works quite well if the original writing media are a typewriter, pencil, or dense ferro-gallic ink. The process uses a Wratten 87 deep red filter in conjunction with Eastman infrared plates and development is carried out in Eastman DK 50 developers. Charred documents are the type of documents found black and brittle in nature because they are accidentally or intentionally exposed to excessive heat.
These documents are very important for investigations, as they may contain important information due to which they were burned. Charred documents can be expected in cases of accidental stack, intentional stack and combustion, insurance and inspection of leaking papers, etc. Wet documents can be examined or deciphered using infrared luminescence technology and infrared photography. Ink has the property of changing the incident visible wavelength to a longer invisible wavelength when light is reflected for it. Infrared can be used to differentiate between inks that look like the eye but differ in infrared fluorescence. A questionable document is any document whose authenticity and/or source is disputed. A questionable document is a document that has linguistic or numerical marks that are affixed to the document by handwriting, printing, typewriter, among others.