1. Fingerprints
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2. Principles of Fingerprints
First Principle: A fingerprint is an individual characteristic; no two fingers have yet been found to posses identical ridge characteristics.
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3. First Principle
The uniqueness of each print is backed up by both mathematical models and real life prints taken in the last 110 years.
The probability of two identical fingerprints in the world is extremely small.
The FBI has 50 million fingerprint records in their database and no two have ever been found to be identical.

4. Determining Individuality
The individuality of a fingerprint is determined by a careful study of its ridge characteristics.
The identity, number, and relative location of characteristics give the print its uniqueness.
If two prints are to match, the characteristics must be identical and have the same relative location to one another.
This type of comparison is called a point by point comparison.
Most judicial systems accept anywhere between 8 to 16 point matches to conclude it is the same print.

5. Principles of Fingerprints
Second Principle: A fingerprint will remain unchanged during an individual's lifetime.
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6. Fingerprint Basics
Our fingerprints are a result of what we call friction skin
It is natures way of giving us a better grasp on our environment
It is a series of hills and valleys called ridges and grooves respectively.
It is these ridges and grooves that you see when you look at an inked fingerprint impression.

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8. Latent Prints
The dermal papillae are responsible for the shape of your fingerprints.
Each ridge has a row of pores that allows sweat to be expelled from the body and deposited on the surface of the skin.
Along with oil that is picked up when we touch the hairy parts of our bodies, this sweat becomes our invisible prints-called latent prints.

9. Obscuring Prints
An injury must reach the dermal papillae layer in order to permanently change the print-about 1-2 millimeters
Impossible to completely change all the characteristics
Scaring just creates new characteristics to identify a person by.

10. John Dillinger
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11. Brain Break: Statuesque Dominoes

12. Principles of Fingerprints
Third Principle: Fingerprints have general ridge patterns that permit them to be systematically classified.
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13. Three Main Types of Prints
Loops
Whorls
Arches
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14. Deltas & Cores
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15. Loops
A loop must have one or more ridges that enter from one side of the print, re-curve, and exit from the same side
One Delta & One Core
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19. Whorls
One or more cores
At least two deltas
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23. Arches
An arch is formed by ridges entering from one side of the print, rising slightly and exiting on the opposite side.
No Deltas & No Cores
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