Fingerprint Patterns and Classification
Fingerprints exhibit patterns that can either be used to narrow the potential source of a latent print, or to exclude an individual as the possible source of a latent print. The three fingerprint patterns—arches, loops, and whorls—can be further broken down into the following sub-patterns: plain arches, tented arches, radial loops, ulnar loops, plain whorls, double loop whorls, central pocket loop whorls, and accidentals. Loops and whorls have a core in the center of the pattern and one or more deltas where the friction ridges making up the pattern diverge. Classification is the process of organizing large amounts of information into categories. Fingerprint classification was historically utilized as a way to organize and file tenprint cards from arrests. The Henry classification system and the NCIC classification system are presented in this chapter, although the Henry system has become obsolete due to the widespread utilization of the Automated Fingerprint Identification System (AFIS).