‘The Science of Fingerprint identification is an exact forensic science and does not admit of any mistake or doubt’
-S Murtaza Fazal Ali, J.
Introduction to Forensic Print Evidence
Fingerprints and finger marks combine to provide the most powerful means of personal identification available to police and courts. these serve as an avenue for forensic science. To be precise, fingerprints are graphic representations of the papillary ridges on the distal phalanges of the fingers of human hands. For every single individual, the thumb impression serves the purpose of a signature. Thumb impressions are an immutable signature that does not change and that cannot be changed under any circumstances. Two persons on this earth cannot have similar fingerprints, neither do the twins even share similar fingerprints and this feature has made the science of fingerprint so unique and reliable.
History of Finger -Print Forensic Evidence
Ancient Babylonians pressed the tips of their fingertips into clay to record business transactions. Thumbprints were used on clay seals in China to ‘sign’ documents. Petro glyph located on a cliff face in Nova Scotia depicts a hand with exaggerated ridges and finger whorls, presumably left by the Mikmaq people. Interest in modern fingerprint identification dates back from 1880. Descriptions of the finer ridges by early anatomists like Nehemiah Grew, Marcello Malpighi, and J.E. Pukinye showed awareness of the intricate makeup of fingerprint patterns.
Sir William James Herschel, the ICS of Bengal, is a prominent name in the world of fingerprint identification. The celebrated film director Satyajit Ray, in his movie ‘The Golden Fortress’ has presented a short and unique introduction of Herschel’s work; where he mentions that it was from Sir Herschel’s letter to the famous English magazine ‘Nature’ in 1880, that we got to know about the use of finger-print as a weapon of identifying criminals.
In 1890, Edward Henry, Inspector General of Police in Bengal, simplified and made a workable achievement in the field of the finger-print system. Khan Bahadur Azizul Haque and Rai Bahadur Hemchandra Bose ‘two Bengal police officers’ made a significant contribution in the classification of the system which came to be known as Henry’s ten-digit classification system. While the formerly contributed perfection of the ten-digit pigeonhole method of classification, the latter evolved a system of sub-classification and a method of single-digit classification.
In 1907, the Central Fingerprints Branch was created in England. So, by the beginning of 20thCentury finger-prints were used in a criminal investigation.
Feature of Finger-Prints Forensic Science
Fingerprints are formed by the deposit of perspiration and fatty matter by the sweat glands in the friction skin of hands, allied with any dirt which happens to be on the fingertips. It is the pattern or design formed by the ridges on the side of the first joint of a finger or a thumb. The ridges form the basis of the science of fingerprints. The ridge characteristics do not undergo any changes throughout the life of a person and remain the same until his death. Skin diseases affect ridges temporarily; after the disease is cured the ridges again regain its normal condition.
Classification of Finger-Prints under Forensic Science
The science of finger-print has evolved a variety of classification systems. The most universal method in India as well as other countries is called the ‘Galton-Henry’ system. While examining the path of ridges it can be found that ridges travel in such a way so as to form a particular shape. The traveling method of ridges is known as a pattern. There are four main types of patterns – loops, arches, whorls, and composite.
In loops, the ridges enter and exist on the same side of the pattern. In arches, the ridges run from one side to another with backward re-curvature. In whorls, at least one ridge must re-curve and make a complete circuit around the core and there are two deltas ordinarily. Composites have characteristics of two or more of the pattern.
Technical Analysis of Finger-Print Impression under Forensic Science
In the technical analysis of fingerprints, three basic factors are to be known. They are – type lines, Cores, and Deltas. The purpose of this classification is simply to provide a method of filing sets of fingers so that these sets of finger-prints can be quickly and early located. This system is especially used in Government Bureaus by which a set of impressions of the same persons are examined for their patterns to which symbols are given. Certain convicted persons are legally bound to give their finger-prints. Each convict gives the impressions of his ten fingers on a card bearing his name, date of conviction, and other particulars. This in the future helps the authorities to match with the impression taken from the place of occurrence of crime.
Indian Evidence Act 1872: Expert Evidence
Section 45 of the Indian Evidence Act, 1872 creates an exception to the general rule that evidence of opinion is not admissible. The Section provides when the court has to form an opinion on a matter of foreign law, science, art, the identity of handwriting or finger impression, the court can seek assistance from skilled persons on relevant fields of expert opinion, Lord Russel asked:
“Is he peritus; is he skilled; has he adequate knowledge?”
A forensic scientist is neither a witness for the prosecution nor for the defense but essentially a witness of the court of law. Hence, the expert must have a special study or experience on the subject and must be qualified to express his opinion.
Another section in the Evidence Act that includes a finger impression is Section 73. The first part of the section provides for the signature, writing, or finger impression purporting to have been written or made by the same person. The second part empowers the court to direct anybody present in the court to give his specimen writing or finger impression for the purpose of enabling the court to compare with others alleged to have been written or made by him.
The opinion of a thumb-impression expert is entitled to greater weight than that of a handwriting expert. His testimony becomes substantive evidence rather than mere expert opinion and is of great value to the case if he can produce enough proof in support of his conclusion. A competent finger-print expert must have both theoretical and practical knowledge of the subject. There is no room for ambiguity.
Whether taking a finger impression of an accused person violates his right against self-incrimination, has been a matter of debate. However, in the verdict of State of Bombay v. Kathikalu Oughad (AIR 1960 SC 1808) the apex court made it clear that giving of thumb impression, handwriting, documents are not personal testimony and they do not come within the meaning of ‘to be a witness’ under Article 20(3), neither do they violate the right against self-incrimination.
Over the years, fingerprint identification has played a crucial role in resolving numerous cases. They are permanent and best-known means for establishing the identity of a person. In the absence of fingerprints, DNA fingerprint is a very useful method. In western countries, DNA fingerprint tests are widely in use. In India also this advanced technology should be inducted for the betterment of court procedure.
- BATUKLAL, THE LAW OF EVIDENCE (Central Law Agency, 22nd ed. 2018)
- CRAIG ADAM, FORENSIC EVIDENCE IN COURT, EVALUATION, AND SCIENTIFIC OPINION (Wiley, 2016).
- FRANCIS GALTON, FINGERPRINTS (MACMILLAN & Co. 1892).
- JAY A. SIEGAL, ENCYCLOPEDIA OF FORENSIC SCIENCE (Academia Press,2nd ed. 2012)
- M. MONIR, TEXTBOOK ON THE LAW OF EVIDENCE (Universal Law Publishing Co. Pvt. Ltd., New Delhi,11th ed. 2018)
- RICHARD SAFERSTEIN, CRIMINALISTICS: AN INTRODUCTION TO FORENSIC SCIENCE (Pearson Education, 12th ed. 2017).
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