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Criminalistics Name:___________________________________ Per:____
H.O.-Fingerprints

History to Fingerprints
Fingerprints left in clay by early artisans and scribes served as a kind of signature.
During China’s T’ang dynasty (8th century AD), clerks used inked fingerprints on business
contracts as a seal of authenticity. A number of people throughout history had commented
on the different ridge patterns, but the science of dactyloscopy, the study of fingerprints,
really started in the 19th century in India with William Herschel.
In 1881, Alponse Bertillon, employed as a ledger clerk at the police headquarters in
Paris, suggested using certain body measurements as discriminating characteristics to
identify habitual offenders. Bertillon first recommended 11 measurements but over the years,
a very consistent method of measurement, description, and classification was worked out,
and by the end of the 19th century, it was accepted almost everywhere. The science of
human measurements is called anthropometry.
France Galton, a British anthropologist, studied both dactyloscopy and Bertillon’s
anthropometry. In 1891 and 1892, he showed how to classify fingerprints using whorls, loops
and arches, as well as a secondary, more complex method. Most important, however, he
showed that a person’s fingerprints stay the same from birth until death, that no two
fingerprints are identical, that prints cannot be altered, and that it is possible to classify a very
large number of prints.
In 1897, Edward Richard Henry, working with Galton, simplified Galton’s system and
established the Henry classification system of identification in India. This replaced Bertillon’s
system. After discovering two individuals with the same Bertillon measurements at
Leavenworth Prison in 1903, the Bertillon system showed its major flaw; however, after
comparing the fingerprints of the two individuals, Will and William West, it was found they
were quite different. Today, most English-speaking countries use some form of the Henry
System.
In the early 1900s, the fingerprint system was adopted by a number of agencies in the
United States. IN 1924 the Identification Division of the FBI was formed; by 1946 it help 100
million fingerprint cards. Currently the FBI has more than 250 million sets of fingerprint
records. If these were all stacked on top of each other, these records would make 133 stacks
as high as the Empire State Building!!!

Fingerprint Evolution
A fingerprint is an impression of the pattern of ridges on the last joint of a person’s finger.
Properties that make a fingerprint useful for identification are:

1. Its unique characteristic ridges
2. Its consistency over a person’s lifetime
3. The systematic classification used for fingerprints.

Humans may have developed fingerprints through evolution. Ridge patterns provide
better grip, makes perspiration easier on a hairless surface, and improve the sense of touch.
The fingers, for example, are so sensitive that a vibration with the movement of 0.02microns
(2x10-5mm) can be detected. Since these friction ridges are created in the womb, no two
fingerprints are alike—not even identical twins! Apes and monkeys also have ridge patterns
on their fingers and toes. Other animals, like cats and dogs, have been shown to have
unique “fingerprints” on their noses!
Fingerprints are able to be “picked up” from object because of the pores that populate the
ridges of our fingerprints. These pores are openings for ducts leading from the sweat glands
below the surface of the skin. Perspiration is discharged through these pores. Whenever we
touch something, the oily moisture is transferred to the surface of the object in an identical
pattern to the ridges on our fingers. Thus, a fingerprint is made.

Classification of Fingerprints
All fingerprints can be classified into three basic patterns: loops, whorls and arches.
1. LOOPS
 This pattern has one or more ridges entering from one side, curving, then going
out from the same side it entered. If even one ridge exits the same side, it
would be a loop.
 There are two subgroups: Radial Loops
and Ulnar Loops
o RADIAL LOOPS-opens toward
the thumb that is the radius, the
shorter of the two bones in the
forearm.
o ULNAR LOOPS-opens toward the
little finger that is the ulna, the
minor bone of the forearm.
(AKA- RADIAL) (AKA-ULNAR)
For a RIGHT HAND FINGERPRINT
 Without knowing which hand made the print, you cannot tell if the loop is radial
or ulnar. Ulnar is more common.
 All loop patterns show a delta, a triangular area usually shaped like the silt
formation near the mouth of a river flowing into the sea.
 Loops also have a core near the center of the pattern.
 The relative location of core and delta are required for complete individual
classification and identification.
 About 65% of fingerprints have loops

2. WHORLS
 There are four subgroups: whorl,
central pocket, double, and accidental.
 All whorls must have at least two
deltas and a core.
 Approximately 20% of fingerprints
have plain whorls.
 Composites (mixtures of two or more
basic patterns) and accidentals (prints
too irregular to fall into any other
group) make up about 10% of all
fingerprints
3. ARCHES
 Least common type of fingerprint and the
simplest of fingerprint patterns but can
be confused with loops by inexperienced
observers.
 The friction ridges enter from one side of
the finger and exit the other while rising
upward in the middle.
 Arches do not have a delta or a core.
 They are divided into two groups: plain
and tented arches

Ridge Classification (individualization)
One must classify fingerprints according to the general patterns or groups listed
above, but to individualize them, you must use the fine structure of ridge characteristics or
minutiae.
There are no legal requirements in the United States on the number of points
(minutiae and relative location) that must match before deciding that a fingerprint belongs to a
certain individual. Criminal courts generally accept 8 to 12 points of similarity as sufficient
proof. Considering there are 150 to 200 minutiae in a properly rolled fingerprint, the problem
is getting a good, readable print to work with.

TYPES OF MINUTIAE
 A BIFURICATION is a branch or forking of a ridge into two ridges.
 A RIDGE ENDING is a termination point of a friction ridge.
 A RIDGE DOT or ISLAND is a ridge feature that resembles a period.
 An ENCLOSURE resembles an
eyelet, and is caused by the legs
of a bifurcation coming together
again to form a single ridge.
 A SHORT RIDGE is one whose
terminal points are very close
together.
 A BRIDGE is a bar linking two
ridges
 PORES in the ridges may be used
for individualization if they are
visible.

Certain professions can affect fingerprints as well. For example, concrete workers and
plasterers’ prints can become indistinct over time because the alkalinity of cement and
gypsum can dissolve proteins.
Primary Classification of Fingerprints
This system is part of the original Henry system and provides the first classification
step in the FBI system. Henry Faulds was a British surgeon working in Tokyo in the 1870’s.
He took up the study of “skin-furrows” after noticing finger marks on specimens of ancient
pottery. He recognized the importance of fingerprints as a means to identification and
devised this method of classification. In 1880 Faulds forwarded his system to Sir Charles
Darwin. Darwin, who was aging and in ill health, passed the material on to his cousin Francis
Galton.

A print is made by starting with the right thumb, followed by each finger in the right
hand. The left thumb followed by each of the left hand fingers is printed next. A number
value is placed on each print that is a whorl according to the table below. A zero is placed
on each print that is a loop or an arch.

16 16 8 8 4
1. Right Thumb 2. Right Index 3. Right Middle 4. Right Ring 5. Right Little
4 2 2 1 1
6. Left Thumb 7. Left Index 8. Left Middle 9. Left Ring 10. Left Little

The values for fingers 2, 4, 6, 8, and 10 are totaled then 1 is added to this value. This
becomes the numerator. The values for fingers 1, 3, 5, 7, and 9 are totaled and then 1 is
added to this value. This becomes the denominator. The primary classification of
fingerprints thus is a fraction showing the relative number of whorls a person has.
Approximately 25% of the population has a 1/1 primary classification. This means they either
have all loops or all arches, or a combination of the two classes.

(2+4+6+8+10) + 1
Primary Classification Number = ------------------------------------
(1+3+5+7+9) + 1