1. Fingerprints
Chapter 6

2. Objectives 1. Discuss the history of fingerprinting.
2. Describe the characteristics of fingerprints.
3. Identify the basic types of fingerprints.
4. Describe how criminals attempts to alter their fingerprints.
5. Determine the reliability of fingerprints as a means of identification.
6. Explain how fingerprint evidence is collected.
7. Describe the latest identification technologies.
8. Determine if a fingerprint matches a fingerprint on record.
9. Use the process of lifting a latent print.

3. History of Fingerprints
Several ancient cultures used fingerprints as markings.
Archeologists discovered fingerprints pressed into clay tablet contracts dating back to BC in Babylon.

4. In ancient China, it was common practice to use inked fingerprints on all official documents, known as early as the 3rd century BC.

5. In the Western world, the earliest record of the study of the patterns in human hands comes from 1684.
Dr. Nehemiah wrote a paper describing the patterns he saw on human hands under a microscope, including ridges.

6. Johann Christoph Andreas Mayer followed that up in by explaining that no 2 people had the same skin ridges!

7. In 1823, Jan Evangelist Purkyn described 9 distinct fingerprint patterns, including loops,spirals, circles, & double whorls.

8. In 1856, Sir William Herschel began collecting fingerprints and noted patterns for each person were different & did not change with age.

9. In Andrew Bertillon (an assistant clerk in the records office at the Police Station in Paris, created a way to identify criminals.
The system, called Bertillonage, was first used in 1883 to identify a repeating offender.
In 1902 he was credited with solving the 1st murder using fingerprints!

10. In 1888, Sir Francis Galton and Sir E. R
In 1888, Sir Francis Galton and Sir E.R. Henry developed the classification system for fingerprints that is still in use today in the United States and Europe.
In Ivan (Juan) Vuctich improved fingerprint collection- he noted measurements on all fingerprint cards.
In Sir Edmund Richard Henry created a fingerprint system that divided fingerprint records into groups based on whether they have an arch, whorl, or loop pattern- CALLED a TEN CARD!

11. Example of a ten card

12. What are FINGERPRINTS?
Fingerprint- raised portion of your skin, arranged in connected units called dermal, or friction, ridges.
When these ridges press against things, they leave a mark, called a fingerprint.
A fingerprint consists of natural secretions from your skin-
Water
Oils
Salts
Dirt (from everyday activities)

13. Formation of Fingerprints
The patterns of fingerprints are formed at the beginning of the 10th week of pregnancy, when the fetus is about 3 inches long.
Occurs in the basal layer of the skin, where new skin cells are produced. Protected by the outer layer
In a fetus this basal layer grows faster than the rest of the skin and “folds” in on itself, creating ridges that cannot be altered or destroyed permanently by skin injuries.

14. Characteristics of Fingerprints - Ridges
Names for their general visual appearance and patterns
Loops (65% of the population)
Whorls (30% of the population)
Arches (5% of the population)
Loop
Whorl
Arch

15. Characteristics of Fingerprints
Arches- have ridges that enter from 1 side of the fingerprint and leave from the other with a rise in the center
Loops- enter from either the right or the left and exit from the same side they enter
Whorls- look like a bulls-eye, with two deltas (triangles)

16. Characteristics of Fingerprints
2 things a forensic examiner looks for on a fingerprint
Core – center of a loop or a whorl
Delta- triangular region located near a loop
Ridge Count – to take a ridge count, an imaginary line is drawn from the center of the core to the edge of the delta

17. Characteristics of Fingerprints
Basic patterns can be further divided
Whorl patterns
Plain whorl (24%)
Central pocket loop whorl (2%)
Double loop whorl (4%)
Accidental whorl (0.01%)

18. Characteristics of Fingerprints- Whorls
Plain Whorl- has 1 or more ridges that makes a complete spiral.
2 deltas & if a line is drawn between them, at least 1 ridge in the inner patterns is touched or cut by the line.
Central Pocket Loop Whorl- Has 1 or more ridges that make a complete circle
2 deltas & if line drawn between them, no ridges in the inner pattern are touched or cut by the line.

19. Characteristics of Fingerprint- Whorls
Double Loop Whorl- has 2 separate loop formations & 2 deltas
Accidental Whorl- has 2 or more deltas & is a combination of 2 of the other patterns (but not plain arch)

20. Characteristics of Fingerprints- Arches
Plain Arches (4%)- show ridges entering one side, rising in the center, & flowing out the other side without making an angle.
No characteristics of the loop pattern
Tented Arches (1%)- does form an angle, or it may possess some characteristic of the loop pattern, such as a delta.

21. Characteristics of Fingerprints
Every individual, including identical twins, has unique fingerprints resulting from unique ridge patterns called minutiae.
There are about 150 individual ridge characteristics on the average full fingerprint.
To match fingerprints, a minimum number of points of comparison are needed.

22. Minutiae Patterns

23. Minutiae Patterns

24. Minutiae

25. Types of Fingerprints 3 Types found by investigators at a crime scene
Patent fingerprints – visible prints left on a smooth surface when blood, ink, or some other liquid comes in contact with the hands & is transferred to that surface
Plastic fingerprints – actual indentions in some soft material such as clay, putty, or wax
Latent fingerprints – (hidden prints)- caused by the transfer of oils & other body secretions onto a surface - invisible
Can be made visible by dusting w/ powders or making the fingerprints more visible by chemical reaction.
Suspect’s fingerprints are taken by rolling each of the 10 fingers onto a ten card.

26. Fingerprint Forensic FAQs
Can Fingerprints be Altered or Disguised?
Not permanently
John Dillinger (Public Enemy No. 1 in the 1930s)
Put acid on his fingertips to change their appearance
Unfortunately they grew back and when he died his fingerprints were taken and compared to known examples he left behind. They were a match!

27. Fingerprint Forensic FAQs
How Reliable is Fingerprinting as a Means of Identification?
Many experts claim it is foolproof but mistakes have been made in the past
Fingerprint examiners are held to high standards and their work is checked and rechecked.

28. Fingerprint Forensic FAQs
How are Fingerprints Analyzed?
Original Henry system – adopted by Scotland Yard in 1901
Converted ridge patters on all 10 fingers into letters & numbers arranged in a fraction - limited
By 1987, the FBI had 23 million fingerprint cards on file & getting a match could take as long as 3 months.
In 1999, the FBI developed the Integrated Automated Fingerprint Identification System (IAFIS or AFIS)
Provides digital, automated, latent searches, electronic storage and exchange of fingerprints & test results
Operates 24 hours a day, 365 days a year
Can get results in 2 hours
Has fingerprints and criminal histories of more than 47 million people!

29. The Future of Fingerprinting
AFIS – Automated Fingerprint Identification Systen
New scanning tech- fingerprints can be scanned at the rate of dots per inch.
Provides an image that reveals minute pore patterns on the fingerprints ridges, allowing for better pattern matching.
New uses
Studies have shown that much of the material we touch daily leaves trace evidence on our fingers and hands which is in turn left on the objects we touch.
Dr. Sue Jickells is doing research to ask how things criminals touch (explosives, cigarettes, drugs, etc) can leave behind traces that can be detected.

30. Methods of Detecting Fingerprints
Fingerprints on hard or nonabsorbent surfaces can be developed by the following manners
Fingerprint powders – gray & black powders are adequate for most latent prints – Use the color that affords the best color contrast.
Magnetic sensitive powders – used on surfaces like leather and rough plastics
Fluorescent powders can be used to photograph latent prints under UV light
Treatment with cyanoacrylate (Super glue)

32. Fingerprints on soft & porous surfaces such as paper, cardboard, & cloth requires treatment with chemicals
Iodine fuming – old method, poisonous fumes
Ninhydrin – chemical reagent used to develop latent prints
Silver nitrate based liquid reagent to visualize latent prints

34. Preserving Fingerprints
Photograph prior to any other process
If the object is small enough to be transported w/o destroying the print, it should be preserved in its entirety.
Prints on large, immovable objects are developed with powder and can be lifted.