Crime Scene Forensics,LLC
Fingerprints
Fingerprints
BASIC FINGERPRINT PATTERNS:
There are three main fingerprint patterns:
1. Loop Patterns:  
In a Loop pattern, the ridges will  flow in one side, recurve, (loop  
around) touch or pass through an imaginary line drawn from the  
delta to the core, and exit the pattern on the same side as it entered.
       
        *A loop pattern has only one delta.
        *There are two types of loop patterns:
               1. Ulnar loop
               2. Radial loop

*Loop patterns account for @ 70% of all fingerprints
2. Whorl Patterns:
A whorl pattern consists of a series of almost concentric circles.
          
           * A whorl pattern has two deltas
           *There are four types of whorl patterns:
                1. Plain whorl,
                2. Central Pocket Loop whorl,
                3. Double Loop whorl,
                4. Accidental whorl

*Whorl patterns account for @ 25% of fingerprints
3. Arch Patterns:
In an arch pattern, ridges flow in one side and flow out the
opposite side. There are no deltas in an arch pattern.

           *There are two types of arch patterns:  
               1. Plain arch,
               2. Tented arch

Arch pattern account for @ 5% of all fingerprints
CLASSIFICATION OF FINGERPRINTS

1. Although the patterns are used primarily to determine a Classification of
the entire Fingerprint card, the patterns are also used for the
individualization of a persons identity.
2. Classification of fingerprints provides for an orderly placing of
fingerprint cards in a file .

Two methods of classifying fingerprints:
1. Henry Classification
2. NCIC Classification
ALL FINGERPRINTS ARE PERMANENT AND INDIVIDUALLY UNIQUE

  • Fingerprints begin forming during the 12th week of gestation, and
    barring surgical or accidental removal of the finger itself, will remain
    permanent for the life of the individual until the body decomposes after
    death.

  • No two fingerprints are alike. No two fingerprints on the same hand are
    alike. Even In the case of identical twins, no two fingerprints are alike.
    Each fingerprint is unique and can only belong to one person.

  • Each fingerprint contains minutiae, or ridge characteristics. Fingerprints
    are identified to individuals by examining and comparing the ridge
    characteristics of two different impressions to determine if these
    characteristics occupy the same relative area and position, and if their
    unit relationship to each other matches.
Type lines
-The two innermost ridges which start parallel, diverge, and             
    surround or tend to surround the pattern area.
-When there is a definite break in a type line, the ridge                     
    immediately outside of it is considered as its continuation.
-The point on a ridge at or in front of and nearest the center of the            
     divergence of the type lines.
-The delta area is located as a triangular area where the ridges                
      radiate outward in three directions.
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