NCJ Number
165218
Journal
Police Chief Volume: 63 Issue: 1 Dated: (January 1997) Pages: 23-28
Date Published
1997
Length
6 pages
Annotation
In the field of forensic fingerprint analysis, there are three stages: the development of the latent fingerprint; the comparison of developed fingerprints with known fingerprints; and the automated storage, retrieval, and comparison of fingerprints. This article focuses on the technology used in the first stage: the visualization of latent fingerprints; cases are cited to show the value of fingerprint evidence in the fight against terrorism.
Abstract
The Identification and Research Branch of the U.S. Secret Services' (USSS) Forensic Services Division is among the leading laboratories involved in the scientific discipline of the visualization of latent fingerprints. In this discipline, scientists begin with a knowledge of what the different components of fingerprint residue are and how they interact or bind with various surfaces. Then they search for or develop sensitive and selective methods to visualize these components on different surfaces. Fingerprint residue consists of water-soluble components (the major ones being inorganic salts, amino acids, and proteins) and water-insoluble components (the major ones being lipids, which include fats). This article describes the USSS's Forensic Services Division's use of ninhydrin analogues to visualize amino acids/proteins from latent fingerprints, along with its benefits. The use of water-based reagents to visualize lipids from latent fingerprints is also discussed. Fingerprint residue contains several organic components. Many of these are strong absorbers of short-wavelength ultraviolet radiation. Among these are some that are fluorescent in the long-wavelength ultraviolet region. The author describes ultraviolet imaging techniques for visualizing latent fingerprints. Also described is the USSS's use of the automated fingerprint information system in the international effort to identify and prosecute terrorists.