Types of Fingerprint Pattern - intoforensics.in

Fingerprint analysis has been used to identify suspects and solve crimes for more than 100 years, and it remains an extremely valuable evidence in court of law to justify the case. Many of us might have wondered how forensic analyst identify criminals with the help of their fingerprints and what the process entails. To put it simply, they look at the patterns of fingerprints. These patterns are little ridges on the end of an individual’s fingers and thumb that are arranged in a pattern of spirals and loops. This patterns are in such the manner that no two human beings have same pattern. Sir Francis Galton first introduced the technique of comparing prints found at a crime scene with those of the suspect. Later, Sir Edward Henry developed the system of classifying fingerprints that was first adopted as the official system in England which eventually spread throughout the world. In the Henry system of classification, there are three basic fingerprint pattern – Loop, whorl and arch.

There is also a complex classification system that break down patterns further.

Arch pattern – Plain Arch and Tented Arch
Loop pattern – Radical loop and Ulnar loop
Whorls pattern
Composites pattern – Central pocket loop whorls, Twin loop whorls, Lateral pocket loop whorls and Accidental loop whorls.

Arch Pattern

Arch are seen in about 5% of fingerprint pattern. The ridges run from one side to the other of the pattern making no backward turn. There is no delta and no recurving ridge must intervene between the core and delta points. There are two types of arch. Plain and Tented.

Plain Arch

Plain arch have an even flow of ridges from one side to the other of the pattern, no significant up thrust and the ridges enter on one side of the impression and flow out the other with a rise or wave in the center.

Tented Arch

They don’t have the same easy flow that pain arch do and have “significant up thrusts” in the ridges near the middle that average arrange themselves on both sides of a spine or axis towards which the adjoining ridges coverage & appear to form tents.

Loop Pattern

These can be seen in almost 60 to 70% of the fingerprints that are encountered. In loop pattern, the ridegs will flow from one side, recurve, touch and pass through an imaginary line drawn from the delta to the core and exit the pattern on the same side form which it entered. Loop pattern only have one Delta. There are two types of Loop.

Radial Loop

Radial loop are named after the radius, a bone in the forearm that joins the hand on the same side as the thumb. The flow of the pattern in radinal loops runs in the direction of the radius (towards the thumb). Radial loop are not very common and most of the time radial loop will be found on the index finger.

Ulnar Loop

Ulnar loop are also named after the ulna, a bone in forearm. The ulna is on the same side as the little finger and flow of the pattern in a ulnar loop runs in the direction of the ulna.

Whorl Pattern

A whorl is that type of pattern in which at least two deltas are present with a recurve in front of each. The type lines for both deltas do not have to be the same ridge. An imaginary line drawn between the two deltas must touch or cross at least one of the recurving ridges within the inner pattern. A recurving ridge, however, which has an appendage connected with it, cannot be construed as a circuit as the recurve is spoiled.

Composites Pattern

These are the pattern combines the features of both loops and whorls. These can be describe in following patterns –

Central Pocket loop Whorl

The pattern looks like a loop but has a small whorl inside the loop ridges. It has two deltas, one at the edge of the pattern area, and one inside the pattern area just below the centermost ridges (inner delta). It fulfills the requirements of the loop with one or more whorl ridges around the core. This pattern is sometimes called a bulb or flower for obvious reasons.

Twin Loop Whorls

A double loop whorl is a pattern that consists of two separate loop formations with two separate and distinct sets of shoulders and two deltas.

Accidental Whorls

An accidental whorl is a pattern consisting of a combination of two different types of patterns, with the exception of the plain arch, with two or more deltas, or a pattern that possesses some of the requirements for two or more different types, or a pattern that conforms to none of the definitions.