Fingerprint Identification

Fingerprints

• Fingerprints are impressions from the papillary ridges on fingers and thumbs.
• Fingerprints are an infallible means of personal identification.
• The ridge arrangement on every finger is unique and doesn't change with age.
• Fingerprints reveal true identity despite personal denial, aliases, or changes in appearance.
• Dactyloscopy is the practice of using fingerprints for identification and is an aid to law enforcement.
• Each epidermal ridge has sweat pores and connects to the dermis via papillae.
• Injuries like burns or cuts won't affect ridge structure unless the dermal papillae are destroyed.
• Ridged areas of the hands or feet can be used for identification.
• Fingerprints are preferred due to the ease of acquisition and recognizable ridge patterns for filing.

Criminal Investigator's Duty

• A criminal investigator's main task is identifying suspects in general.
• Cases of unknown suspects are where actions are known, but personal identification is lacking.
• Witnesses describing physical features provide for positive identification of a suspect
• Tracing information is all information indicative of an individual's personal identity and is another means of identification

Finger Anatomy

• Fingers are limbs used for manipulation and sensation, found on hands of humans and primates.
• Fingers function to grip objects.
• The distal phalanges are fat on thier palmar surface, small, and with a roughened, elevated surface.
• The middle phalanges, known as intermediate phalanges, connect proximal and distal phalanges.
• Proximal phalanges form the base of each toe, they are separate bones to the middle and distal phalanges

Palm Anatomy

• The palm is the underside of the hand, known as the broad palm/metacarpus.
• It is located between the phalanges and carpus.
• The interdigital palm region represents approximately 30% of the palm area.
• The thenar refers to a group of muscles on the palm at the base of the thumb.
• The hypothenar is a group of three muscles that control the movement of the little finger.
• Hands are important for touching, grasping, feeling, holding, manipulating and caressing.

Allied Sciences of Fingerprint

• Dactyloscopy is the practical application of fingerprint identification by the examination and comparison of fingerprints
  • "Dactyl" is Greek for finger
  • "Skopien" is Greek for examine
  • Juan Vucetich Kovacevich is the Father of Dactyloscopy
• Chiroscopy is the study of the palm of the hand
  • "Cheir" is Greek for hand
  • "Skopien" is Greek for study.
  • William J. Herschel is the Father of Chiroscopy
• Podescopy is the study of foot prints
  • "Podo" is Greek for foot
  • "Skopien" is Greek for study
  • Edmond Locard is the Father of Podescopy
  • He is also known as the Sherlock Holmes of France
• Poroscopy is the study of the arrangements of sweat pores.
  • "Poros" is Greek for pare
  • "Skopien" is Greek for study
• Dactylography is the science dealing with fingerprint identification, embracing dactyloscopy, poroscopy, chiroscopy, and podoscopy
• Dactylomancy is the study of fingerprints used for personality interpretation
  • "Derma" is Greek for skin
  • "Glype" is Greek for carve
• Ridgediology is the study of poroscopy, edgeoscopy, and ridge characteristics used for fingerprint identification.
• Fingerprint uniqueness are determined by the pattern ridges and valleys as well as minutiae points where the ridge structures change

Different Finger Conditions

• Polydactyly/lism is a condition where babies are born with extra fingers and is often common in families
• Syndactyl is a condition where children are born with fused/webbed fingers
• Branchdactyl is a term for fingers/toes that are shorter than normal
  • It is also known as "short digits"
  • This condition is caused by gene mutation that affects bone growth
• Ectrodactyl is a condition characterized by the absence/malformation of fingers/toes
  • It is also known as split hand/foot malformation (SHFM)
• Macrodactyl is a condition where a baby's toes or fingers are abnormally large due to the overgrowth of underlying bone and soft tissues

Application to Law Enforcement

• Fingerprints are used to identify criminals at crime scenes.
• They are used to identify fugitives through fingerprint comparison.
• They are used to assist prosecutors by defending cases using defendant records
• Fingerprints provide identification data to probation/parole officers and parole boards for decision making.
• Fingerprints are exchanged with foreign identification bureaus in cases of mutual interest.
• Fingerprints serve as a means of personal identification.
• Fingerprints are used for the identification of unknown deceased individuals.
• Fingerprints prevent hospital mistakes in infant identification
• Fingerprints are used to identify persons with amnesia if their fingerprints are on file.
• Fingerprints are used to identify missing persons.
• Fingerprints are used for personal identification in disaster work.
• Fingerprints are used in licensing procedures for automobiles, firearms, aircraft, and other equipment.
• The purpose of fingerprints provides the means for personal and criminal identification.