The Individuality of Fingerprints: The fingerprints are capable of endless variation so that
it has been speculated that there is one chance in sixty-four billions of two persons having identical
Quetlet’ s rule states that every nature-made objects present infinite variation in forms and no
patterns are ever alike.
(1) The latent print (chance print) is an invisible or barely visible impression left on a smooth
(2) Visible prints are formed by fingers stained with blood or ink or other medium.
(3) The plastic print is an impression made on a soft surface, such as soap, cheese, mud, pitch,
candles, thick dried blood, adhesives, etc.
MUTILATION OF FINGERPRINTS: Criminals sometimes attempt to mutilate the pattern by
self-inflicted wounds or burns, application of corrosives or erosion against a hard surface.
Permanent impairment of the fingerprint pattern occurs in
- electric injurv
- after exposure to radiation.
In infantile paralysis, rickets and acromegaly, though the pattern is not altered, the distance
the ridges can be changed.
Computerisation: Fingerprint reader (FINDER) is a computerised automatic fingerprint reading
system which can record each fingerprint data in half second. Prints of eight fingers are recorded
excluding little fingers. The light reflected from a fingerprint
can be measured and converted to digital data which is classified, codified and stored in the
In criminals, impressions of all the ten fingers are taken, but for civil purposes, the left thumb
impression only is taken.
(1) The recognition of impressions left at a scene of crime, e.g., on weapons, furniture, doors, utensils,
clothes, etc., establish the
identity of the criminal.
(2) The identification of suicides, deserters, persons suffering from loss of memory or those dead or
unconscious after being involved in an accident and of decomposing bodies.
(3) Identification in case of accidental exchange of
( 4)The prevention of impersonation.
(5) To maintain identity records.
(6) Cheques, bank notes and other legal documents can bear a fingerprint. Rough idea about the age
of a finger print can be made
by studying the migration of chloride ions from the fingerprint.