Types of questioned documents – forensic document examination gas x reviews ratings


Questioned Document Examination is a branch of forensic science that deals with documents having a suspicious authenticity. electricity physics pdf Also called as Forensic Document Examination, it involves the application of scientific methods and principals for document examination. This helps to produce evidence about a questioned document that is admissible in the court of law to prove its legitimacy.

Sometimes even documents that do not bear any visible mark is subjected to forensic document examination. For example, documents kept below other documents while writing may contain impression evidence. Even burned or shredded documents can give significant leads to an investigation if they are reconstructed. Applications of Questioned Document Examination

Document Examiners have a crucial role to play in investigations involving a documentary evidence. Say a suicide note is found at the investigation scene. electricity electricity lyrics Forensic Document Examination helps answer questions whether the note was written by the deceased or someone trying to manipulate investigators? In such cases, handwriting examination is applied to compare the handwriting with original samples collected from the scene.

Handwriting and signature are unique to a particular individual. This makes it possible for document examiners to identify forgery or alterations. Document examiners trained in handwriting and signature analysis are thus able to identify a forged handwriting/signature from a genuine one. Examination of Printers, Fax Machines, Typewriters and Photocopy Machines

In the case of typewritten questioned documents, Document Examiners go to the extent of examining the very machines that produced them. For instance, a typewriter output always has certain exclusive properties. electricity symbols ks3 Some of these properties are the same for a particular model of the machine – electric/manual, carbon film ribbon/fabric ribbon etc. Typewriters, printing or photocopy machines also produce unique properties on its output depending on its abuse, damage, wear and tear. electricity and circuits class 6 Ink Examination

Document examiners sometimes use liquid chromatography to extract samples of ink from a questioned document for analysis. Other methods of ink examination include subjecting the questioned document to infrared radiation. This helps identify forged documents because different inks react differently when exposed to different frequencies of infrared light. Detection of Indentation

Documents recovered from a crime scene or a suspect may also give crucial leads from impression evidence or indented writing. gasco abu dhabi contact Certain documents do not contain any distinguishing mark or note. However, when analyzed with an Electrostatic Detection Device (EDD), they reveal certain invisible impressions or indentations. These could help establish crucial links between a suspect and the crime. Detection of Deletions, Erasures and Other Alterations

Forensic Document Examination can reveal for evidence of alterations, obliterations, erasures and page substitutions. Such changes that are not visible to the naked eye can be detected using photography and UV/IR imaging devices. Imaging instruments such as a Video Spectral Comparator (VSC) use radiations of different wavelengths to identify additions, erasures or alternations. This is possible by the different reactions of different inks to varied wavelengths of light.