FRSC 1011H Chapter Notes - Chapter 8: Digital Imaging, Digital Image, Alphonse Bertillon
2 May 2018
School
Department
Course
Professor
Fingerprints
Fundamental Principles of Fingerprints
● Fingerprints are a production of friction skin ridges found on the palm side of the
fingers and thumb.
● The basic principles underlying the use of fingerprints in criminal investigations
are as follows:
○ A fingerprint is an individual characteristic because no two fingers have
yet been found to process identical ridge characteristics
○ A fingerprint remains unchanged during an individual's lifetime
○ Fingerprints have general ridge patterns that permit them to be
systematically classified.
● All fingerprints are divided into three classes in the basis of their general pattern
○ Loops
○ Whorls
○ Arches
● The individuality of a fingerprint is determined not by its general shape or pattern
but by a careful study of its ridge characteristics. The expert must demonstrate a
point by point comparison in order to prove the identity of an individual.
● A four step process known as ACE-V (analysis, comparison, evaluation, and
verification) is used to identify and individualize a fingerprint.
● The final step in the process involves verification of the examiner’s conclusion by
a second examiner.
● When a finger touches a surface, perspiration and oils are transferred onto that
surface, leaving a fingerprint. Prints deposited in this manner are invisible to the
eye and are commonly referred to as “latent” or “invisible” fingerprints.
Classification of Fingerprints
● The primary classification is the first step in classifying fingerprints under the FBI
system. The presence or absence of the whorl pattern is the basis for the
determination of the primary classification.
Automated Fingerprint Identification Systems
● The fingerprint database known as AFIS convert an image of a fingerprint into
digital minutiae that contain data showing ridges at their pints of termination
(ridge endings) and of branching into two ridges (bifurcations)
● AFIS makes no final decisions on the identification of a fingerprint, instead
leaving this function to a trained examiner.
Document Summary
Fingerprints are a production of friction skin ridges found on the palm side of the fingers and thumb. The basic principles underlying the use of fingerprints in criminal investigations are as follows: A fingerprint is an individual characteristic because no two fingers have yet been found to process identical ridge characteristics. A fingerprint remains unchanged during an individual"s lifetime. Fingerprints have general ridge patterns that permit them to be systematically classified. All fingerprints are divided into three classes in the basis of their general pattern. The individuality of a fingerprint is determined not by its general shape or pattern but by a careful study of its ridge characteristics. The expert must demonstrate a point by point comparison in order to prove the identity of an individual. A four step process known as ace-v (analysis, comparison, evaluation, and verification) is used to identify and individualize a fingerprint.
