Fingerprinting

Fingerprints, first introduced to police procedure by E.R. Henry*, provide an infallible means of identification, because the individual’s fingerprint (made up of patterns made by the ridges on the fingertip skin) is unique and does not change with growth or age.

The FBI recognizes eight different types of ridge patterns: radial loop, ulnar loop, double loop, central pocket loop, plain arch, tented arch, plain whorl and accidental. Loops make up about 65% of total fingerprint patterns, whorls about 30% and arches 5%. The most common pattern is the ulnar loop.

At the scene of crime, latent prints have to be made visible before they can be collected. This is usually done by brushing them with gray or black powder containing chalk or lampblack mixed with other materials. The prints made visible in this way are either photographed or lifted on the adhesive surface of sticky tapes. At the end of the 20^th century, FBI files held fingerprint records of more than ninety million people.

ONELINER: Fingerprinting

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BIBLIOGRAPHY:

Encyclopedia Britannica