1. T. Trimpe 2006 http://sciencespot.net

2. Fingerprint Principles According to criminal investigators, fingerprints follow 3 fundamental principles: A fingerprint is an individual characteristic; no two people have been found with the exact same fingerprint pattern. A fingerprint pattern will remain unchanged for the life of an individual; however, the print itself may change due to permanent scars and skin diseases. Fingerprints have general characteristic ridge patterns that allow them to be systematically identified.

3. 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

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

5. Arches Arches are the simplest type of fingerprints that are formed by ridges that enter on one side of the print and exit on the other. No deltas are present. 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. Spike or “tent”

6. Loops Loops must have one delta and one or more ridges that enter and leave on the same side. These patterns are named for their positions related to the radius and ulna bones. Delta 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. NOTE: On the left hand, a loop that opens to the left would be an ulnar loop, while one that opens to the right would be a radial loop.

7. Whorls Whorls have at least one ridge that makes (or tends to make) a complete circuit. They also have at least two deltas. If a print has more than two deltas, it is most likely an accidental. 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. Plain Whorl Central Pocket Whorl

8. Whorls – Part 2 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. Double Loop Whorl Double loop whorls are made up of any two loops combined into one print. Delta

9. Identify each fingerprint pattern. Right Hand Left Hand Right Hand

10. Bertillon System First systematic attempt at personal identification Consisted of: –precise measurements of body parts (anthropometry) –Detailed description of the subject –Full length photograph System was Flawed…

11. Case Study of Bertillon System Will West Case: 1903 Will West went to Leavenworth Penitentiary in Kansas. The records clerk thought he looked familiar, but he denied every being incarcerated. Prison officials investigated and found another William West at Leavenworth with the exact same Bertillon measurements as Will West. The two Wests denied being brothers or having any knowledge of each other. Fingerprints helped distinguish between the two Wests. The Bertillon System was immediately dumped

12. History of Fingerprints Cont… 1880 – Faulds (a surgeon) writes that fingerprints can be used for personal ID. 1892 – Galton published the first text book on fingerprints (“Finger Prints”) –Described patterns, established that no two prints were identical, and prints remained unchanged throughout life. 1899 – Sir Edward Henry devises a classification on 5 types of prints –A modified system of the Henry classification system is used by the FBI today in the US. 1910 – Thomas Jennings was the first person convicted for murder in Chicago on fingerprint evidence – LANDMARK CASE.

13. Bertillon’s 2 nd Big Mistake ! 1910 – Bertillon adds fingerprints to his Bertillonage profile but only includes the right hand…. BIG MISTAKE! Case Study: 1911 –Da Vinci’s Mona Lisa was stolen. –Left at the crime scene was a thumbprint of the left hand of the criminal. –Bertillon did not have data for the left hand and the perpetrator was not found for another two years.

14. John Dillinger Case Study In an effort to avoid police, underwent facial plastic surgery and tried to remove his fingerprints by burning them off with acid. Despite his efforts… prints taken at the morgue still matched the ones on file.

15. Composition of Skin Skin is composed of layers of cells –Epidermis – closest to the surface –Dermis – inner skin –Dermal Papillae – area in between the Epidermis and Dermis. Determines the ridge pattern Develops in the human fetus In order to change the pattern, damage would have to penetrate 1 to 2mm beneath the skin’s surface (OUCH) and then the scars would become a pattern – efforts to change are futile!

16. Methods of Detecting Prints 1.Visible Prints – contact with colored material such as paint, blood, grease, or ink leaves a noticeable print. 2.Plastic Print – impression left on a soft material such as putty, wax, soap, or dust 3.Latent Prints – caused by the transfer of body perspiration or oils on fingers to an object (Invisible to the eye) Need a developer to aid in discovery

17. Developers for Nonporous/Nonabsorbent Surfaces Super Glue – cyanoacrylate reacts with sodium hydroxide releasing a vapor that binds with the amino acids forming a white latent print. Powder – adheres to oils and moisture in the prints making it visible. (The color of powder used, depends on the material where the print was left.) RUVIS – Reflected Ultraviolet Imaging System, detects print in its natural state by aiming UV light at the prints.

18. Developers for Porous/Absorbent Surfaces Iodine Fuming – iodine vapors combine with oils to visualize prints. (Must be photographed immediately…will disappear over time.) Ninhydrin – forms purple-blue color with amino acids present in perspiration. (Most popular method.) Physical Developer – silver nitrate- based chemical mixture used to visualize prints. Shown to be effective at visualizing prints that are undetected by other methods.

19. Fingerprint Processing Should not be preformed at the crime scene. Items should be submitted to the lab Once latent prints are visualized they must be permanently preserved for future comparison and possible use in court as evidence. (Usually photographed) Fingerprints can now be enhanced for the most accurate and comprehensive analysis using digital imaging.

20. It’s time to make some prints! Avoid Partial Prints GOOD PRINT Get as much of the top part of your finger as possible!

21. Directions 1 st – Roll the “pad” portion of your thumb over the ink pad from the left side of your thumb to the right. You do not have to push down really hard! 2 nd – Roll the “pad” portion of your thumb from the left side of your thumb to the right in the correct box on your paper to make a thumbprint. 3 rd – Continue this process to make a fingerprint of all ten fingers on the “My Prints” worksheet. 4 th –Use your notes and a magnifying lens to help you figure out what type of pattern is found in each of your fingerprints. Label each one with the pattern’s name.

22. Minutiae There are as many as 150 ridge characteristics on an average print Most of the time only partial prints are recovered at a crime scene There is no set criteria number of characteristics that must match to consider prints the same. Generally 8-16 matches found by an expert are considered a good match.

23. Fingerprints are unique Composed of friction ridges which give us better gripping ability (tire treads). Results in patterns and minutiae

24. Minutiae There are as many as 150 ridge characteristics on an average print Most of the time only partial prints are recovered at a crime scene There is no set criteria number of characteristics that must match to consider prints the same. Generally 8-16 matches found by an expert are considered a good match.

25. Bifurcation – a single friction ridge that has split into two Ridge ending – the point where a friction ridge ends Short ridge – a single friction ridge that runs only a short distance

26. Dot (island) – a friction ridge that is about as long as it is wide Enclosure – a single ridge that splits in two and then comes back together to form a single ridge again Spur – a bifurcation in which one of the ridges ends after a short distance

27. Crossing – two ridges that cross over one another and form an X Crossover – a short ridge that runs between two parallel ridges

28. Fingerprint ridge characteristics