Fingerprints History and Anatomy All Rights Reserved South-Western / Cengage Learning © 2012, 2009 Forensic Science: Fundamentals & Investigations, Chapter 6

Historical Development 3rd century B.C. in China—oldest known documents Ancient Babylon (1792-1750 B.C.)—fingerprints pressed into clay tablets marked contracts 1684—Dr. Nehemiah Grew’s paper describes the patterns on human hands, including the presence of ridges 1788—Johann Mayer noted that the arrangement of skin ridges is never duplicated in two persons #3 is actually Dr. Nehemiah Grew. Forensic Science: Fundamentals & Investigations, Chapter 6

Historical Development 1823—Jan Evangelist Purkinje describes nine fingerprint patterns; none are in use today 1856—Sir William Herschel (right) began the collection of fingerprints and noted they were not altered by age 1883—Alphonse Bertillon used anthropometry to identify criminals that were repeat offenders using 11 body measurements #5 is Johannes Purkinje. And you might want to mention that none of his nine patterns are used today. You might also want to mention that Bertillon’s method (called anthropometry) had nothing to do with fingerprints (although it’s important in fingerprint history). Hos method involved taking 11 different anatomical measurements of his subjects. Forensic Science: Fundamentals & Investigations, Chapter 6

Historical Development 1888—Sir Francis Galton (r) identified and named minutiae patterns and Sir Edmund Richard Henry developed the fingerprint classification system still used in the US 1891—Iván (Juan) Vucetich collected all ten fingerprint impressions and noted measurements. He was the first to use fingerprints in a criminal case in 1892 1896—Sir Henry, with two colleagues, created a system that divided fingerprints into groups. All ten fingerprints are imprinted on a card (called a tenprint card) along with other notations #8. Galton (who was Charles Darwin’s first cousin) didn’t develop the system of classification we use today. He played around with some pattern classification, but he’s really known for naming the minutiae that you have on slide #18. Henry (along with his minions) did develop the system that’s still in use today. #9 Vucetich developed his own classification system that was used in Argentina. And it was Vucetich that made the first fingerprint identification in a criminal case in 1892. That identification, plus Vucetich’s classification system led to the abolishment of Bertillon’s anthropometry system in Argentina in favor of fingerprints. Then the rest of the countries followed suit. #10 The card displaying impressions of all ten fingers is called a Tenprint Card.

Example of a Tenprint/10-Print Card Again, this would be called a Tenprint Card or a 10-Print Card. Forensic Science: Fundamentals & Investigations, Chapter 6

Levels of Organization in the body Multicellularity makes possible a division of labor at the cellular level Cells, tissues, organs, and organ systems maintain relatively stable internal environments

What Are Fingerprints? All fingers, toes, feet, and palms are covered in small ridges Ridges help us grip objects Ridges are arranged in connected units called dermal, or friction, ridges Fingers accumulate natural secretions and dirt Fingers leave prints on objects we touch Did you mean leave or create? Forensic Science: Fundamentals & Investigations, Chapter 6

Structure of Skin: Anatomy Glands: Eccrine: secretes largely water, with both salts and amino acids. Found on palms of hands, feet. Most important for fingerprints. Apocrine: secretes pheromones and other organic materials. Found in axial and genital regions. Sebaceous: secretes fatty or greasy substances. Sprouts a hair. The inorganic substances from eccrine glands are primarily salts and amino acids.

Structure of Skin: Anatomy Layers of skin: Epidermis: outermost layer, provides a waterproof barrier Dermis: beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands. Subcutaneous tissue (hypodermis): is made of fat and connective tissue.

Structure of Skin: Fingerprints Location of Sweat Glands: Most numerous in the palms and the soles, where they open on the summits of the papillary ridges. Stimulus Responses: The chief stimuli to sweating are heat, emotion, and gustatory perspiration (eating spicy foods). Emotional perspiration occurs characteristically on the forehead, axillae, palms, and soles. I might add gustatory perspiration (from eating spicy foods), although heat and nervousness apply most to suspects committing crimes. Forensic Science: Fundamentals & Investigations, Chapter 6

Fingerprint Formation 1. Basal layer grows faster than the layers above and below it 2. Basal layer collapses and folds to form intricate shapes Fingerprints are made of an arrangement of ridges, called friction ridges. Each ridge contains pores, which are attached to sweat glands under the skin. You leave fingerprints on glasses, tables and just about anything else you touch because of this sweat.

Inheritance of Fingerprints Do Intro to Fingerprints Family Activity Read Scientific American: Inheritance of Fingerprints article Forensic Science: Fundamentals & Investigations, Chapter 6

Classification of Fingerprints Forensic Science: Fundamentals & Investigations, Chapter 6

Characteristics of Fingerprints There are 3 general fingerprint distinctions: ARCH About 5% WHORL About 30% LOOP About 65% of the population Forensic Science: Fundamentals & Investigations, Chapter 6

Characteristics of Fingerprints Forensic examiners look for Core (the center of a whorl or loop) Deltas (whorls/loops) (triangular regions near a loop) Ridge count Counting the number of ridges between the core to the edge of the delta Distinguishes one fingerprint from another although many have same ridge count The cores, deltas, and ridge counts are used primarily in fingerprint classification, although they can be used as part of a fingerprint examination (comparison and identification). Deltas are found in whorl patterns as well as loop patterns. The ridge count (which is actually the number of ridges between the core and the delta) can distinguish between some fingerprints, but there are many fingerprints out there that have the same ridge count. Forensic Science: Fundamentals & Investigations, Chapter 6

Characteristics of Fingerprints Plain Whorl There are actually 4 sub-categories of whorls. The one that isn’t shown here is the Plain Whorl. Forensic Science: Fundamentals & Investigations, Chapter 6

Characteristics of Fingerprints Tented arches can be tricky. The one shown here does not have a delta. But there is one type of tented arch that MAY have a delta. The subject may be too complicated (and too boring) to be introduced in this class. Forensic Science: Fundamentals & Investigations, Chapter 6

Characteristics of Fingerprints Basic patterns can be further divided: Loops (60-65%) Arch patterns (5%): 4% plain 1% tented Whorl patterns (30%): 2% central pocket 4% double loop 0.01% accidental % plain whorl Even twins have unique fingerprints Again, there are actually 4 different whorls. And there are also 2 different types of loops. I don’t see that mentioned here. Forensic Science: Fundamentals & Investigations, Chapter 6

Fingerprint Minutiae Patterns The accepted terminology today is: 1. ending ridge. 2. bifurcation. 3. short ridge. 4. dot. 5. bridge (or crossover). 6. spur. 7. island (sometimes, enclosure). 8. This would really just be considered two bifurcations. 9. A delta is not one of the minutiae. This is a dot and a bifurcation. 10. trifurcation. 2 Forensic Science: Fundamentals & Investigations, Chapter 6

Types of Fingerprints There are 3 types of prints that investigators look for at crime scenes: Patent fingerprints—visible prints Contaminated print: visible prints transferred onto smooth surfaces by blood or other liquids Plastic fingerprints—indentations left in soft materials such as clay or wax Latent fingerprints—made visible by dusting with powders or the use of chemicals Patent prints are considered to be visible prints. So plastic prints are a sub-category of patent prints. #1 is actually describing something called a contaminated print, which is also a sub-category of patent prints. Forensic Science: Fundamentals & Investigations, Chapter 6

Fingerprint Forensic FAQs How are latent fingerprints collected? You can speed up the development of a print treated with ninhydrin by applying heat and humidity. A steam iron works great for this. The other name for cyanoacrylate fuming is superglue fuming. Cartridge cases also work well with silver nitrate. You might mention that iodine sublimates, much like dry ice. Forensic Science: Fundamentals & Investigations, Chapter 6

Fingerprint Forensic FAQs Can fingerprints be erased? Only temporarily; they will grow back if removed with chemicals. EXCEPTION! If you damage the dermal layer of skin Is fingerprint identification reliable? Yes, but analysts can make mistakes Can computers perform matches in seconds? No, but the FBI’s Integrated Automated Fingerprint Identification System (IAFIS) and the Automated Fingerprint Identification System (AFIS) can provide a match in 2 hours They can actually be erased if you get into the dermal layer of the skin. AFIS is actually the acronym for the Automated Fingerprint Identification System (which is a little different from IAFIS). Forensic Science: Fundamentals & Investigations, Chapter 6

The Future of Fingerprinting New scanning technologies Yield detail in minute patterns Reduce analytical mistakes Analyze trace elements of objects on the skin Technologies that recognize patterns in Retina Face Veins in your palm Forensic Science: Fundamentals & Investigations, Chapter 6

Types of Prints and Developing

Latent Prints Not visible to the naked eye. Consist of the natural secretions of human skin glands Eccrine: secretes largely water, with both salts and amino acids. Found on palms of hands, feet. Most important for fingerprints. Apocrine: secretes pheromones and other organic materials. Found in axial and genital regions. Sebaceous: secretes fatty or greasy substances. Sprouts a hair.

Developing Latent Prints Idea is to make print stand out against its background Requires substances that interact with secretions Lasers and alternative light sources are used to view (find!) latent fingerprints in conjunction with other methods. May be necessary to attempt more than one technique, done in a particular order so as not to destroy the print. LASER’s and ALS’s are usually used in conjunction with other methods. Very few fingerprints will have inherent luminescence (luminesce on their own).

Physical Developing Dusting/Powders: adhere to both water and fatty deposits. Choose a color that contrasts with background. Use on rigid/non-porous material such as glass, plastic, or metal Dust adheres to oil and sweat left behind Dusting is not considered a chemical method (as the title of the slide says) because there’s no chemical reaction. It’s considered a physical method. Do you mean rigid/non-porous instead of ridged/non-porous?

How to roll fingerprints: http://www.youtube.com/watch?v=d7N-4UNAzsw How to dust for prints: https://www.youtube.com/watch?v=FMhuEjmRB-4 How to lift prints: http://www.youtube.com/watch?v=FMhuEjmRB-4 How to roll fingerprints: http://www.youtube.com/watch?v=d7N-4UNAzsw

Chemical Developing Iodine Fuming Ninhydrin Silver Nitrate Cyanoacrylate (super glue) Forensic Science: Fundamentals & Investigations, Chapter 6

Iodine Fuming Iodine: fumes react with oils and fats to produce a temporary yellow-brown color. Use on porous and non-porous surfaces such as paper, index cards, magazines, and cardboard Sweat and oil will absorb iodine vapors

Ninhydrin Ninhydrin: reacts with amino acids to produce a purple color. Use on porous surfaces such as paper, tissue, and clothing

Chemical Developing Silver nitrate: reacts with chloride to form silver chloride, a material that turns gray when exposed to light. Cyanoacrylate: “superglue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit. The students may find it amusing to learn that if you heat superglue too much it turns into cyanide gas.

Iodine Fingerprint

Ninhydrin Fingerprint

Cyanoacrylate Fingerprints

Other Types of Prints Lips: several common patterns 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

Palm Prints friction ridges can be identified and may be used against suspects

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

AFIS Automated Fingerprint Identification System Uses scanner to convert image to digital minutiae that can be compared With AFIS: takes 20 minutes to search L.A. fingerprint database. Without AFIS: takes 67 years IAFIS—the FBI’s Integrated Automated Fingerprint Identification System, which is a national database of 10-print cards from all over the country Not all fingerprint cards are in IAFIS.

Lip Prints I think I once dated the one on the top right. 