June 27, 2013
Pratt, A. (2012). Fingerprints and firearms. Journal of Forensic Identification, 62(3), 234-242. Retrieved from http://search.proquest.com/docview/1018428076?accountid=9971
Fingerprints and Firearms
Advancements in today’s technology and knowing that each person has their own distinctive set of fingerprints have given new developments in the world of criminal justice. Fingerprints have become the most positive proof when it comes to identification. For a long time in the criminal justice system, before fingerprint identification, the system relied upon the system that Alphonse Bertillon developed to identify criminals. Now, fingerprinting has been accepted worldwide as a method of identification in criminal investigations. This article review discusses the history of fingerprints, explanation of latent prints, and the recovery rate of identifiable latent prints on firearms evidence. Also discussed are the factors that may affect the deposition of a fingerprint.
History of Fingerprints In 1883 Alphonse Bertillon developed the first systematic attempt at personal identification (Saferstein, 2011). The Bertillon system relied on a detailed description (portrait parlé) of the subject, combined with full length and profile photographs and a system of precise body measurements known as anthropometry (Saferstein, 2011, p. 390). This system gave the criminal justice system an effective way to identify individuals. Bertillon system was used and considered the most accurate way of identification for 20 years. Saferstein (2011) stated “In the turn of the new era law enforcement became reliant on the use of finger ridge patterns known as fingerprints as the new way of establishing identifications” (p.390, para. 3). There are three fundamental principles of fingerprints. The first being that a fingerprint is an individual characteristic; there are no two people with the exact same fingerprint pattern. The second is a fingerprint pattern remains unchanged for the life of an individual from the day they are born. The only way for possible changes is due to permanent scars and diseases. Lastly the third principle is fingerprints have general characteristic ridge patterns that allow them to be systematically identified. The classes of ridge patterns are arches, loops and whorls. Approximately 60% of people have loops, 35% have whorls, and 5% have arches (Trimpe, 2009).
Fingers and toes are covered by sweat glands, which explain why when one sweat and they touch a surface a print is left. Latent prints are prints left by the deposit of oils and/or perspiration, which is invisible to the naked eye (Saferstein, 2011, p. 393). A latent print comes from skin under ones toes, feet and fingers. This skin is called the friction ridge skin, which consists of raised areas of skin called ridges and the space in between the ridges are called furrows. During the development of the fetus is when ridge details form. As stated before every person has their own unique ridge detail and as they grow and age the ridge detail does too.
Recovery Rate of Identifiable Latent Prints on Firearms Evidence
Pratt (2012) stated that the fingerprint specialists at the Bureau of Alcohol, Tobacco, Firearms and Explosives Forensic Science Laboratory in San Francisco process firearms evidence on a daily basis (p. 235). They start by looking for the presence of fingerprints. All components of the firearms are separated and placed in a Foster Freeman cyanoacrylate chamber at 80% humidity with hard evidence liquid glue (Pratt, 2012, p. 235, para. 1). The fumes from the chamber interact with the fingerprint residue, turning the friction ridges white. Rhodamine 6G is then applied, it stains the residue while under a different light source, which then increases the contrast and visualizations of the prints.
Pratt (2012) stated that on the