Fingerprinting

Fingerprinting

Overview

1. Fingerprints offer an infallible means of personal identification.

2. It is the essential explanation for establishing identities of criminals reluctant to admit previous arrests.

• Fingerprinting has servered all governments worldwide during the past 100+ years to provide accurate identification of criminals. 

• No two fingerprints have ever been found alike. Even comparing billions of fingerprints. 

• Fingerprints are the very basis for the foundation of criminal history at every police agency.

• Fingerprints remain the most commonly used forensic evidence worldwide. 

• In most jurisdictions, fingerprint examination cases match or outnumber all other combined forensic examination casework. 

• Fingerprints outperform DNA and all other human identification systems to identify more murderers, rapists, and other serious offenders. 

• Fingerprints solve ten times more unknown suspect cases than DNA in most jurisdictions. 

• Visible human characteristics change; fingerprints do not. 

• Before the mid-1800s, law enforcement officers with extraordinary visual memories identified previously arrested offenders by sight “camera eyes” 

• Photography came next but wasn’t very efficent because looks changed. 

The History of Fingerprinting

• 1,000-2,000 B.C: 

  • In ancient Babylon, fingerprints were used on clay tablets for business transactions.

• 3rd Century B.C:

  • Thumbprints were used on clay seals in China to “sign” documents.

• Malpighi (1686):

  • A professor of anatomy at the University of Bologna, noted that ridges on the hands are for grip and the ridges on the feet are for tractions.

  • He also noted spirals and loops in fingerprints from using a microscope.

• Purkinje (1823):

  • Published his thesis discussing 9 fingerprints patterns, but he too made no mention of the value of fingerprints for personal identification.

  • His observation started to lay groundwork for organization and filing. 

How to Fingerprint

• There are two types of impressions involved in taking fingerprints

• The upper ten are taken individually (thumb, index, middle, ring, and little finger of each hand) and are referred to as the “rolled” impressions because the fingers rolled from one side of te fingernail to the other, in order to obtain all available ridge detail.

• The impressions at the bottom of the card are taken simultaneously without rolling, they are called “plain,” “slapped,” or “flat” impressions

• The plain impressions are used to verify the  sequence and accuracy of the rolled impressions. 

Steps for Fingerprinting

1. Fingers to be printed must be clean and dry.

2. The individual should be asked to stand to the right and at arm’s length from fingerprint device.

3. Individual needs to be relaxed and have him/her focus on another object away from the device.

4. Grasp the hand at the base of their hand, and cup the individuals fingers, guide the fingerm and roll it.

5. The ink should cover from one edge of the nail to the other, as well as the joint crease.

6. Roll the finger from side to side in appropriate space and lift finger when removing to prevent smearing.

The History of Fingerprinting

• Sir William Herschel (1858):

  • He first used hand prints to sign contracts with native indians

  • The English felt that using this method made the contract more binding and personal.

  • He started to realize that all fingerprints were different.

  • Herschel’s fingerprinted himself for 50 years apart and realized that they did not change. 

  • Herschel began to note that the inked impressions could, indeed prove or disprove identity, but did not say it.

  • He noted that fingerprints were unique to the individual and permanent throughout life.

• Dr. Henry Faulds (1880):

  • A british surgeon who discussed fingerprints as a means of personal identification, and the use of printers ink as a method for obtaining fingerprints.

  • He is credited with the first fingerprint identification: a greasy print left by a laboratory worker on a bottle of alcohol. 

Bertillon System

• Alphonse Bertillon (1882):

  • Devised Anthropometry, a system to measure and record the dimensions of 11 body parts of prisoners.

  • These measurements were reduced to a formula which, theoretically, would apply to one person and would not change during his/her adult life.

  • For 30 years, the Bertillon System was used to identify people. Until Will West was sentenced to the U.S. Penitentiary in Leavenworth, Kansas. It was discovered that him and another prisoner had the same measurements and a similar name William West. 

Upon investigation, there were indeed two men that looked exactly alike. Their names were Will and William West. Their Bertillon measurements were close enough to identify them as the same person. However, a fingerprint comparison quickly and correctly identified them as two different people. They had been  identical twins that were separated at birth.