FREE ESSAY ON FINGERPRINTS

FINGERPRINTS

Fingerprints are one of the most important things that link a suspect with a crime scene.
Even though that fingerprints are not always left by a criminal, the crime scene should
still be examined for them. All people have distinct friction ridges on the skin of the
fingers. In leaving an impression, an outline of the ridges is transferred and duplicated
by oil, sweat and other substances on the object handled. The impression is usually not
visible. Fingerprints not visible are called latent prints; so something must be done to
make them visible. 
The most common way to make them visible is to dust an object with fingerprint powder.
The color of the powder should contrast with the surface, such as black powder on
light-colored backgrounds and white powder on dark. An alternative to using powders, is
using chemicals. The most common to use are Iodine, ninhydrin, silver nitrate, or
cyanoacrylate esters. The process involves fuming, spraying, brushing, or dipping the
object in a solution of the chemical. Yet another way to make fingerprints visible is to
use radiation. There are two kinds of radiation to use, Ultraviolet rays, and laser
radiation.
A latent print requires a suitable surface for it to be picked up. Porous surfaces such
as unpainted wood and some kinds of paper are unlikely to yield a useful impression.
Smooth surfaces like glass, enamel, and glossy paper are ideal to lift the print if you
are lucky enough to get it.