Tag Archives: questioned document examination

Application of UV Light in Questioned Document Examination

Ultraviolet (UV) illumination techniques are used for multiple purposes in forensic science examinations. It includes; Duplicate Paintings, Forged Signatures, documents in question, ink examination, latent fingerprints examination, detecting ink stains and identifying trace of body fluid at crime scene or on clothes.

The Questioned Documents can consist of identification of any type of fake or genuine documents, such as; stamps, will, sale deed, bank checks, handwritten letters, printed documents and digital documents, etc.

Detection of forgeries in documents under long and short wave ultraviolet light usually examine several Documents in question.

UV is the significant sources of radiation which is widely used in Questioned Document examination. It is also generated by specialized arcs and lights such as mercury-vapor lamps, tanning lamps, and black lights.

Ultraviolet light also known as ultraviolet radiation is a form of energy which is a part of the electromagnetic spectrum. Ultraviolet (UV) is a 10 nm to 400 nm wavelength electromagnetic radiation that is shorter than visible light but longer than X-rays(visible light ranges from 400 nm to 700 nm, and infrared light ranges from 700 nm to 1200 nm).

Ultraviolet radiation is produced by natural sources, such as; the sun (It contributes about 10% of the Sun’s overall electromagnetic radiation production) and artificial ones, such as black light tubes, mercury vapor lambs, and electronic flashes, and it is often accompanied by visible light.

The ultraviolet portion of the spectrum has been divided into three regions:
1. Short wavelength: It ranges from 180 to 280 nm. It is used in Following work: Sterilisation, Chromatography, Mineralogy and Photochemical reactions, etc.

2. Medium wavelength: It ranges from 280 nm to 320 nm. For Medium wave transmission of UV a quartz lens is required. Sun lamps are artificial sources for this type of radiation and it is used for cosmetic and therapeutic purposes;

3. Long wavelength: It ranges from 320 nm to 400 nm and also known as near ultraviolet. This UV region is produced by portable lamps and can be very beneficial to the forensic experts for document examinations.


UV radiation is used for many types of Suspected Document examination, Some are listed below:

1.In examination of Paper: Differently manufactured papers give different fluorescence under UV rays. UV rays are very much beneficial to recognize the different materials of paper by producing various fluorescence for example, it may appear greenish in some cases while it can be reddish in other cases.

2. In examination of Inks: Fountain pen inks of different brands have different composition in addition to their similar colors when examined under UV light.

3. In Examination of Counterfeited Document: UV radiation will give different fluorescence with different sizing and fibers present in the document. authentic documents use different types of sizing, inks, different colors of fibers, Specific watermarks (Chemical and Mechanical), and papers, etc. in printing while duplicators can’t use the same source so these minute details can be detected by UV light. Generally, Following types of documents are prepare in duplicate: Fake currency notes, security papers, passports, certificates, etc.

4. In Examination of Alterations in Documents: If document has been treated with anytype of chemical eraser or mechanical eraser then spots will be visible under UV light.

5. In Examination of Secret Writings: The secret writing can be made using biological fluids like urine, milk, saliva, semen, vegetable and plant juices, and quinine hydrochloride, etc. All of these produce specific fluorescent under UV light, Which makes it easier for expert to decipher that hidden content.

6. In examination of Resealed Envelope: An envelope that is opened and re-sealed with any type of glue can fluorescent differently under UV light.

7. In examination of duplicate or forge Paintings: Forgers always try to make duplicate copy of famous paintings and try to showcase them as original work. These type of forgery are easy to detect with the help of UV light. different paint colors give different fluorescent, specially paints used on an old painting will fluoresce differently than modern. 2nd important thing is to detect the paper of painting, aging of paper can easily examined under UV light radiation.

8. In Examination of Stamp, Bank notes, Credit cards,etc.: With the help of UV light many more document forgeries can be determine.

Examination of Questioned Document (Chapter 2)

Questioned document examination (QDE) is the examination of documents Which are potentially disputed in a court or according to the law. This branch or division is come under Forensic Science.

Purpose of Questioned Document Examination

A document may be examined for a different reasons which serve the purpose to differentiate between authenticated and forged documents using scientific processes and methods. including:

  • Identity of the author.
  • To compare typewritten or computer printer-generated documents.
  • True contents of the document.
  • Analyze inks and papers.
  • Origin of the instrument of paper used in making the document.
  • Determine the age of a document.
  • Uncover credit card forgeries and currency fraud,
  • Alterations or erasures which have been made.
  • Authenticity of the document.
  • Reconstruct charred or obliterated writing.
  • Seals and Stamps
  • Indented Writing, etc.

Section related to Questioned Documents under Indian Penal Code,1860

Our Law gives us several provision related to documents in question.

Several sections of the Indian Penal Code, 1860 deals with a forged or questioned document. Following are the relevant sections:

  • Section 465 : Punishment for forgery—Whoever commits forgery shall be punished with imprisonment of either description for a term which may extend to two years, or with fine, or with both.
  • Section 466 : Imitation of a record of a Court of Justice or of a Registrar of Births, etc., held by a public servant.
  • Section 471 : Using a forged document as genuine.
  • Section 472 : Developing or counterfeiting a seal, plate, etc., with the intent of committing a forgery punishable under section 467 of the IPC, or possessing with like intent any such seal, plate, etc., knowing the same to be forged.
  • Section 489 A : Counterfeiting bank or currency notes.
  • Section 417 : Punishment for cheating—Whoever cheats shall be punished with imprisonment of either description for a term which may extend to one year, or with fine, or with both.

Several sections of the Indian Evidence Act, 1872 deals with a forged or questioned document. Following are the relevant sections:

Section 3: “Document.”— “Document” means any matter expressed or described upon any substance by means of letters, figures or marks, or by more than one of those means, intended to be used, or which may be used, for the purpose of recording that matter.

  • Section 61: Proof of contents of documents
  • Section 64: Proof of documents by primary evidence
  • Section 65: Cases in which secondary evidence relating to documents may be given
  • Section 65A: Special provisions as to evidence relating to electronic record
  • Section 65B: Admissibility of electronic records
  • Section 67: Proof of signature and handwriting of person alleged to have signed or written document produced
  • Section 67A: Proof as to digital signature
  • Section 73A: Proof as to verification of digital signature.

Tools and Techniques used in Examination

The most important tool which document examiner has is his/her own vision, that is the first instrument which examiner use to examine the sample at first. Then according to the need examiner decide to use the external tools which enable the examiner to see, evaluate and record more than is visible to the normal eye. These tools can be divided into 6 class:

1. basic measuring tools

2. magnification (magnifiers/microscopes)

3. light sources

4. special instruments

5. photography equipment

6. computer equipment

Here, Some Equipments or special instruments name are mentioned which are used to examine questioned documents are following:

  • Stereo Microscope

  • Microspectrophotometers

  • Uv-Vis-Nir, Ftir And X-Ray Fluorescence Spectrometry

  • Video Spectral Comparator

  • Electrostatic Detection Apparatus

  • Thin Layer Chromatography:

  • High Performance Thin Layer Chromatography

  • High Performance Liquid Chromatatography

  • Fourier Transform Infrared Microscopy

  • Raman Spectroscopy

  • Digital Hyperspectrum Equipment And Software For Forensic Documentexaminers

  • Docubox Dragon Projectina 1

  • Pyrolysis Gas Chromatography- Mass Spectrometry

  • Inductive Couple Plasm- Mass Spectrometry

  • Neutron Activation Analysis

Process for examination of document:

A Questioned document examiner makes scientific analysis, comparison and examinations of documents in question in order to:

Establish genuineness or non-genuineness, or to expose forgery, or to reveal alterations, additions or deletions,

1. Questioned document examiner Identify or remove a persons as the source of handwriting,

2. Questioned document examiner identify the source of typewriting or other impression, marks, or relative evidence, and,

3. Questioned document examiner also write reports and give testimony, when needed in court.

A scientific method of Questioned Document Examination consist of the followings steps to examine:

Analysis – First of all examiner observe every detail of sample from his eyes with the help of magnifier.

Comparison – After Analysis Examiner determine the Properties and characteristics of the questioned sample and compare it with known sample.

Evaluation – After analysis and comparison Document examiner need to evaluate the characteristics and properties of questioned sample and standard sample so that each details of samples can be determined.

Questioned Document Examination (Chapter 1)

Question: What is Document?

Answer: A word Document is refer to something that contains information. That information can be held on wax, tapes or stored electronically. In another words documents are those which is not only made of paper but also other materials which can bear written messages for example boards, walls or even bodies can bear written messages.

Section 3 of Indian Evidence Act, 1872 defines Document as, “Document” means any matter expressed or described upon any substance by means of letters, figures or marks, or by more than one of those means, intended to be used, or which may be used, for the purpose of recording that matter.

Illustrations –

A writing is a document;

Words printed, lithographed or photographed are documents;

A map or plan is a document;

An inscription on a metal plate or stone is a document;

A caricature is a document.

(look at the below for continue pages)

Read more : Questioned Document Examination (Chapter 2)