1. Chapter 4: Fingerprints “Fingerprints can not lie, but liars can make fingerprints.” —Unknown

2. Chapter 41 Fingerprints  Why fingerprints are individual evidence.  Why there may be no fingerprint evidence at a crime scene.  How computers have made personal identification easier. Students will learn:

3. Chapter 42 Fundamental Principles of Fingerprints  A fingerprint is an individual characteristic.  A fingerprint will remain unchanged during an individual’s lifetime.  Fingerprints have ridge patterns that allow them to be classified and entered into a national database.

4. Chapter 4 Interesting Info Did you know? Dactyloscopy is the study of fingerprint identification. Police investigators are experts in collecting “dactylograms”, otherwise known as fingerprints. 60% of people have loops, 35% have whorls, and 5% have arches

5. Chapter 44 Ridge Characteristics Minutiae—characteristics of ridge patterns  Ridge ending  Short ridge  Dot or fragment  Bifurcation  Double bifurcation  Trifurcation  Bridge  Island  Enclosure  Spur

6. Chapter 45 Fingerprint Minutiae

7. Chapter 4 Fingerprint Classes There are 3 specific classes for all fingerprints based upon their visual pattern: arches, loops, and whorls. Each group is divided into smaller groups as seen in the lists below. Arch Plain arch Tented arch Loop Radial Loop Ulnar loop Whorl Plain whorl Central pocket whorl Double loop whorl Accidentical

8. Chapter 47 Arch  An arch ridges that enter on one side of the print and exit on the other.  No deltas are present.  Types:  Plain  Tented

9. Chapter 4 Arch Types 8 Plain Arch Ridges enter on one side and exit on the other side. Tented Arches Similar to the plain arch, but has a spike in the center. “tent”

10. Chapter 49 Loop  A loop must have one or more ridges entering and exiting from the same side.  Types:  Radial—opens toward the thumb  Ulnar—opens toward the “pinky” (little finger)  Which type of loop is this, if it is on the right hand? Left hand?

11. Chapter 4 Loop types 10 Ulnar Loop (Right Thumb) Loop opens toward right or the ulna bone. Radial Loop (Right Thumb) Loop opens toward the left or the radial bone. Delta

12. Chapter 411 Whorl  A plain or central pocket whorl has at least one ridge that makes a complete circuit.  A double whorl is made of two whorls.  An accidental is a pattern not covered by other categories.  Whorls have at least two deltas and a core.  Types  Plain  Central Pocket  Double Loop  Accidental

13. Chapter 4 Plain Whorl Central Pocket Whorl 12 Draw a line between the two deltas in the plain and central pocket whorls. If some of the curved ridges touch the line, it is a plain whorl. If none of the center core touches the line, it is a central pocket whorl.

14. Chapter 4 Kendall/Hunt Publishing Company 13 Double Whorl Double loop whorls are made up of any two loops combined into one print. Delta Accidental Whorl Accidental whorls contain two or more patterns (not including the plain arch), or does not clearly fall under any of the other categories.

15. Chapter 4 Identify each fingerprint pattern. Right Hand Left Hand Right Hand

16. Chapter 4 Fingerprint Comparison  There are at least 150-200 individual ridge characteristics on the average fingerprint.  8 to 12 specific points that match exactly are required by most criminal courts as a positive ID. 15

17. Chapter 416 AFIS  The Automated Fingerprint Identification System - a computer system for storing and retrieving fingerprints  By the 1990’s most large jurisdictions had their own system in place. The problem - a person’s fingerprints may be in one AFIS but not in others  IAFIS—the FBI’s Integrated Automated Fingerprint Identification system which is a national database of all 10-print cards from all over the country

18. Chapter 4 3 Kinds of CRIME-SCENE Prints  1. VISIBLE PRINTS which are prints made by fingers that touched material such as blood, paint, grease, or ink.  2. PLASTIC PRINTS which are ridge impressions left on a soft material such as putty, wax, soap, or dust.  3. LATENT PRINTS which are invisible print impressions caused by the perspiration on the ridges of one’s skin. Perspiration contains water, salt, amino acids, or oils and easily allows impressions to be made.

19. Chapter 418 Latent Prints  Latent fingerprints are those that are not visible to the naked eye.

20. Chapter 419 Developing Latent Prints  Developing a print requires substances that interact with secretions that cause the print to stand out against its background.  It may be necessary to attempt more than one technique, done in a particular order so as not to destroy the print.  Powders—adhere to both water and fatty deposits. Choose a color to contrast the background.  Iodine—fumes react with oils and fats to produce a temporary yellow brown reaction.

21. Chapter 420 Developing Latent Prints  Ninhydrin—reacts with amino acids to produce a purple color.  Silver nitrate—reacts with chloride to form silver chloride, a material which turns gray when exposed to light.  Cyanoacrylate—“super glue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit.

22. Chapter 421 Iodine Fingerprint

23. Chapter 422 Ninhydrin Fingerprint

24. Chapter 423 Cyanoacrylate Fingerprints

25. Chapter 424 Primary Classification The Henry—FBI Classification Each finger is given a point value rightleft

26. Chapter 425 Primary Classification Assign the number of points for each finger that has a whorl and substitute into the equation: right right left left left index ring thumb middle little + 1 right right right left left thumb middle little index ring +1 That number is your primary classification number =

27. Chapter 426 Other Prints  Ears—shape, length and width  Voice—electronic pulses measured on a spectrograph  Foot—size of foot and toes; friction ridges on the foot  Shoes—can be compared and identified by type of shoe, brand, size, year of purchase, and wear pattern.

28. Chapter 427 Other Prints Palm—friction ridges can be identified and may be used against suspects.

29. Chapter 428 Other Prints Footprints are taken at birth as a means of identification of infants.

30. Chapter 429 Other Prints Lips—display several common patterns  Short vertical lines  Short horizontal lines  Crosshatching  Branching grooves

31. Chapter 430 Other Prints Teeth—bite marks are unique and can be used to identify suspects. These imprints were placed in gum and could be matched to crime scene evidence.

32. Chapter 431 Other Prints The blood vessel patterns in the eye may be unique to individuals. They are used today for various security purposes.

33. Chapter 432 Biometrics  Use of some type of body metrics for the purpose of identification. (The Bertillon system may actually have been the first biometry system.)  Used today in conjunction with AFIS  Examples include retinal or iris patterns, voice recognition, hand geometry  Other functions for biometrics—can be used to control entry or access to computers or other structures; can identify a person for security purposes; can help prevent identity theft or control social services fraud.

34. Chapter 4 Kendall/Hunt Publishing Company 33 More about Prints For additional information about prints and crime, check out Court TV’s Crime Library www.crimelibrary.com/criminal_mind/forensics/fin gerprints/1.html