Laboratory Assignment Fingerprints

Forensics Student Manual 3 Copyright Information Forensics Lab Manual © 2015 eScience Labs, LLC. All rights reserved. This material may not be repro-duced, displayed, modified, or distributed, in whole or in part, without the express pri-or written permission of eScience Labs. Appropriate citations must accompany all ex-cerpts and/or quotations. For written permissions, please contact [email protected] Note: Educational institutions and customers who have purchased a complete lab kit may reproduce the manual as a print copy for academic use provided that all copies include the following statement: “© 2015 eScience Labs, LLC. All rights reserved”. This manual was typeset in 11 Arial and 12 Chalet-London 1960. Arial font provided by Microsoft Office Suite, 2010. Chalet-London 1960 font licensed from House Indus-tries, 2011. The experiments included within this lab manual are suitable for supervised or unsu-pervised learning environments. eScience Labs assumes full liability for the safety and techniques employed within this manual provided that all users adhere to the safety guidelines outlined in the mandatory eScience Labs Safety Video, Preface, and Appendix. All users must understand and agree to the eScience Labs safety guide-lines prior to beginning their lab experiments. eScience Labs does not condone use of the lab materials provided in its lab kits for any use outside of the curriculum express-ly outlined within the lab manual. 5 Acknowledgements Acknowledgements The Forensics Lab Manual is a collaborative development which we are delighted to provide to higher education curriculum. Key contributors, including Cindy Higgins (M.S., Educational Instructional Design and Technology) and Dr. Max Houck (Ph.D., Forensic Chemistry), have brought creativity, rigor, intelligence, and industry applica-bility to this lab kit. We have greatly enjoyed working with this team, and look forward to serving students around the world with our hands-on lab experiments. 7

Table of Contents

Forensics Lab Manual

Table of Contents Fingerprinting

sing Your Lab Kit

Using Your Forensics Lab Kit

o successfully use and get the most learning and enjoyment out of your Forensics lab

kit here are some tips before you begin:

 Re

fer to your course’s syllabus for the due date and sequence of your lab as-

signments. Your instructor may not assign all of the labs or may not assign

them in the order they are presented in the lab manual, on the Student Portal,

or your school’s Learning Management System (LMS).

 As soon

as you receive your kit, compare the contents of your kit to the inven-

tory insert that comes in your kit. If you are missing any items or any item was

broken during delivery call eScience Labs at 1-888-375-5487 or email

[email protected] immediately for a replacement.

 Th

ere are a few materials that you will need to complete your experiments

that are not provided in your kits such as fresh produce or water. Review the

Time and Materials section (after these tips) for a list of these items.

 Th

e Time and Materials section also includes an estimate of the amount of

time it will take a student to complete each lab to help you plan to set aside

time to complete them. Some experiments may require a few days to a week

for observation, so don’t wait until the last minute to begin experiments.

 Before

performing an experiment, read through the procedure thoroughly so

that you know what to expect when you begin to handle materials.

Most importantly, have fun! 11 Time and Materials Time and Materials Required There may be a few additional materials required to complete your lab experiments which are not included in your eScience Labs kit. Please review the procedures and plan accordingly. Note that the times listed are approximations and may differ de-pending on the assignments required by your instructor and/or your previous subject knowledge. Evidence and Crime Scenes Time Required: 1 hour Additional Materials: Camera (camera phones are acceptable), Scissors, Blue or Black Ink Pen, Computer, Internet Access Fingerprinting Time Required: 1.5 hours Additional Materials: Camera (camera phones are acceptable), Right Hand Fingerprints, Left Hand Fingerprints, Paper Towel or Clean Towel, Soap and Water (for hand washing), Work Surface (See Step 1 in Experi-ment 1 Procedure), Glass Surface (window, bottle, etc.), Metal surface (chair, door knob, etc.), Skin Oil (from face) Blood Time Required: 1.5 hours Additional Materials: Camera (a camera phone is acceptable), Paper Tow-els, Pencil, Adjacent Floor and Wall, Flat Surface If you are allergic to nitrile, please contact eScience Labs at [email protected] and we will send you an alternative type of safety gloves. Some of your kit materials, such as rubber bands, may include latex. Always wear your nitrile safety gloves when working with these items! 12 Time and Materials Impression Evidence: Shoes, Tires, Tools Time Required: 1 hour Additional Materials: Camera (a camera phone is acceptable) 13 Safety Information Lab Safety Always follow the procedure in your laboratory manual and these general rules: Lab Preparation  Please thoroughly read the experiment procedure before starting.  If you have any doubt as to what you are supposed to be doing and how to do it safely, please STOP and then:  Double-check the manual instructions.  Check www.esciencelabs.com for updates and tips.  Contact us for technical support by phone at 1-888-ESL-Kits (1-888-375-5487) or by email at [email protected].  Read and understand all labels on chemicals.  If you have any questions or concerns, refer to the Material Safely Data Sheets (MSDS) available at www.esciencelabs.com. The MSDS lists the dangers, storage requirements, exposure treatment and disposal instructions for each chemical.  Consult your physician if you are pregnant, allergic to chemicals, or have other medi-cal conditions that may require additional protective measures. Proper Lab Attire  Remove all loose clothing (jackets, sweatshirts, etc.) and always wear closed-toe shoes.  Long hair should be pulled back and secured. All jewelry (rings, watches, necklaces, earrings, bracelets, etc.) should be removed.  Safety glasses should be worn at all times. In addition, wearing soft contact lenses while conducting experiments is discouraged, as they can absorb potentially harmful chemicals.  When handling chemicals, always wear the protective glasses, gloves, and apron pro-vided in your safety kit. 14 Safety Information Performing Experiments  Do not eat, drink, chew gum, apply cosmetics, or smoke while conducting an experi-ment.  Work in a well ventilated area and monitor experiments at all times, unless instructed otherwise.  When working with chemicals:  Never return unused chemicals to their original container to avoid contamination.  Never place chemicals in an unmarked container to avoid identification or proper disposal problems.  Always put lids back onto chemicals immediately after use to avoid contamination or potential hydration problems.  Never ingest chemicals. If this occurs, seek immediate help. Call 911 or “Poison Control” 1-800-222-1222  Never leave a heat source unattended.  If there is a fire, evacuate the room immediately and dial 911. Lab Cleanup and Disposal  If a spill occurs, consult the MSDS to determine how to clean it up.  Never pick up broken glassware with your hands. Use a broom and a dustpan and discard in a safe area.  Do not use any part of the lab kit as a container for food.  Safely dispose of chemicals. If there are any special requirements for disposal, it will be noted in the lab manual.  When finished, wash hands and lab equipment thoroughly with soap and water. Above all, use common sense. Read the manual carefully and pay close atten-tion to the safety concerns prior to starting an experiment. 15 Student Portal Student Portal Resources You can find supplemental resources including, videos, simulations, and tutorials on the eScience Labs Stu-dent Portal. The following list outlines available resources by lab: Evidence and Crime Scenes Evidence and Crime Scenes Concept Animation Evidence and Crime Scenes Lab Drill Virtual Microscope Fingerprinting Fingerprinting Concept Animation Fingerprinting Lab Drill Blood Blood Concept Animation Blood Lab Drill Impression Evidence: Shoes, Tires, Tools Impression Evidence: Shoes, Tires, Tools Concept Animation Impression Evidence: Shoes, Tires, Tools Lab Drill Access your Student Resources with these easy steps: If you purchased a kit directly from www.eScienceLabs.com, your user account already has access to the Student Resources for your course. To access these, please visit www.eScienceLabs.com, and click on the Stu-dent tab. Then, enter your username and password. On the following page, scroll down until you see the name of your lab kit or prod-uct SKU. This should be a hyperlink. Click this hyperlink. You will see a series of topics, each of which contain lab information or virtual as-sets. If you purchased a kit from somewhere else (e.g., your bookstore), you’ll need to set up a new user account. Begin by going to www.eScienceLabs.com, and clicking the Cre-ate Account button in the upper right-hand corner. After you are registered and logged in, click the HAVE A CODE button, located on the right side of the home page. Enter the access code located on the underside of your lab kit box lid and press Submit. Click on the Student tab from the home page. On the following page, scroll down until you see the name of your lab kit or product SKU. This should be a hyperlink. Click this hyperlink. You will see a series of topics, each of which contain lab in-formation or virtual assets. Lab Fingerprinting 39 Fingerprinting Fingerprinting Learning Objectives  Explain the role of fingerprints in forensics  Perform a fingerprint rolling technique and analyze minutiae  Collect a fingerprint sample using a dusting technique Introduction The patterns of raised skin found on the fingers of every individual are known as fingerprints (Figure 1). Fingerprints develop in the womb, and except for changing in size during growth, the pattern of each fingerprint will remain the same throughout a person’s life. They are biometrics, measurable biological features used for identi-fication purposes. Forensic investigators utilize fingerprints to cor-roborate evidence that a suspect was present at a crime scene. If fingerprints are properly collected and in good condition to be ana-lyzed, they may be admissible in court. Skin and Fingerprints The skin consists of three layers of tissue: the epi-dermis, dermis, and hypodermis (Figure 2). The epidermis is the outermost layer of skin, and cer-tain areas have a feature called friction ridge skin. The palms of the hands, fingers, soles of the feet, and toes have raised lines called ridges and grooves. Depressed areas between the ridges are called furrows. Friction ridge skin, along with pores (the tiny openings in the skin that secrete sweat and oils), allow the hands and feet to firmly grasp surfaces. Friction ridge skin forms in the 12th to 16th week of fetal development through a combi-nation of genetic and environmental factors. There-fore, a person’s genetic make-up is coded to dic-Epidermis Dermis Hypodermis Pore Figure 2: Basic skin anatomy. Is fingerprint evidence always admissible in court? Knowledge Check! Figure 1: A fingerprint. 40 Fingerprinting Fingerprinting tate how friction ridge skin will form, but random events, such as the fetus’s position at a particular moment or the composition and density of surrounding amniotic fluid, influences how every individual’s fingerprints form into a distinctive pattern. Fingerprint Characteristics Print ridges on finger tips are found in basic patterns with small, distinguishable variations known as minutiae (Table 1). The three basic patterns of finger friction ridge skin in-clude: Loop: Ri d g es ent er fr om o n e s i d e of t h e fi n ger (either left or right), form a loop or hairpin turn, and exit from the same side of the finger tip from which they entered. Loop patterns can be further classified as radial loops (enter and exit toward the thumb) or ulnar loops (enter and exit toward little finger). More than 50% of people have looped fingerprints, mak-ing it the most common pattern (Figure 3). Figure 3: Loop ridge pattern. The area shaded red highlights the looped shape. Table 1: Common Ridge Minutiae Name Illustration Bifurcation (Fork) Double Bifurcation Dot Delta Ridge Ending Eye Bridge Island Spur Trifurcation 41 Fingerprinting Fingerprinting Whorl: Ri d g es f or m alm o s t c o n c en tr i c ci r c l es o r s pi r al s i n t h e c en ter of t h e fi n g er ti p. Who r l s can be further classified as plain whorls, central pocket loops (one ridge that makes a complete circuit without touching another ridge), double loops (two loops within the whorl), and accidental whorls (combination of other patterns). About 30% of people have whorl ridge patterns (Figure 4). Arch: Ri d g es ent er fr om o n e s i d e of t h e f i n g er ti p, cr eat e a w ave o r ten t s h ap e, an d exi t o n t h e opposite side from which they entered. Arch patterns can be further classified as plain arches or tent-ed arches (sharper rise than plain arch). This is the least common fingerprint pattern (Figure 5). Figure 4: Plain whorl ridge pattern. Figure 5: Plain arch ridge pattern. 42 Fingerprinting Fingerprinting Collecting Fingerprint Evidence Forensics can identify a victim, suspect, or witness by the ridge pattern that remains when a fingertip comes into contact with an object. Fingerprint residue varies, but is typically a combination of sweat, oil, dust, or other residue. A latent fingerprint is not visible to the naked eye. Specialized lighting or chemicals may be applied to areas suspected of containing latent fingerprints. In contrast, patent prints are visible to the naked eye. For example, if someone touches a substance, such as blood, grease, ink, or paint, and then touches a wall, tool, or other surface, a visible print is transferred to the object. Another type of visible fingerprint impression is a plastic print, w hi c h i s a t h r ee-dimensional fingerprint impression left in a material, such as soap. The characteristics of the surface where a latent print is found determine which evidence collection method is used to document the print. For non-porous, smooth surfaces, such as a metal window sill, an investigator may use powder processing, in which a surface is dusted with a powder that sticks to fingerprint residue to reveal the fingerprints (Figure 6). The prints can then be lifted with an adhesive tape or photographed. Finger-print powders are produced in a variety of colors to allow for the best contrast when photographing and observing prints. For porous surfaces, such as paper, technicians may use a substance that will seep into the surface grooves, such as a gel-lifter. Technicians may also use chemi-cals that react with fingerprint residue to reveal fingerprints. The re-vealed prints can then be documented with photography. One example of a chemical that reveals latent fingerprints is ninhydrin, which binds to chemicals in the fingerprint residue and turns purple. Another example is silver nitrate, which reacts with salt in sweat residue to form silver chlo-ride. When exposed to ultraviolet light, the fingerprint is visible as a sil-ver color. Recovering fingerprint impressions from fabric surfaces is more difficult than smooth, non-porous surfaces, but techniques used on plastics can reveal latent fingerprints. One example is vacuum metal deposition, which uses fine layers of gold and zinc in a heated vacuum chamber. For plastic, glass, metal, or other hard surfaces, cyanoacrylate, a compound commonly found in Super Glue®, can be heated to reveal prints. The fumes released from heating bind to fingerprint residue in a fume chamber, polymerize, and leave a chalky deposit that can be photographed. Lighting techniques also are one of the dozens of ways used to make la-tent prints visible. Figure 6: A police officer uses a powder processing technique to reveal latent fingerprints on a win-dow sill. Is there one method for collecting fingerprints? Why or why not? Knowledge Check! 43 Fingerprinting Fingerprinting Fingerprint Analysis Not all fingerprints collected at a crime scene can be used to find a match to a suspect. Partial fingerprints or fingerprints collected from certain surfaces that result in a poor quality print may not reveal enough ridge de-tail to distinguish minutiae. In addition to the quality of a collected fingerprint, there are other factors that need to be considered when analyzing a fingerprint. While it is accepted that fingerprints are unique to every per-son, \no scientific studies have confirmed the uniqueness of a fingerprint or defined a standard for what con-stitutes a match. For some prints, eight points may be sufficient. Others may require more to support a con-clusion. Examiner skill, experience, subjectivity, and bias may also affect the determination of a fingerprint match. There have been cases in which multiple experienced fingerprint analysts have declared a match be-tween a fingerprint and a suspect who was later proven to be not guilty. Computer programs, such as the Integrated Automated Fingerprint Identification System (IAFIS) used by the FBI and state and local authorities, are used to standardize fingerprint analysis and aid in narrowing possible matches from millions of fingerprints in a relatively short amount of time. While a Scottish medical missionary in Japan, Henry Faulds (1843-1930) studied fingerprints and estab-lished dactylography, the study of fingerprints for identification purposes. He tested whether fingerprints could be changed by shav-ing, sanding, and burning the skin among other re-moval techniques. They could not: the same pat-terns returned after the fin-gers healed. Image Source: http://commons.wikimedia.org/Figures in Forensics 44 Fingerprinting Fingerprinting Experiment 1: Finger Rolling Technique and Minutiae Identiﬁcation In this experiment, you will practice rolling your fingerprints. For the purposes of performing this experiment, you will take your own fingerprints. Note that when a person has their fingerprints taken, they do not partici-pate in the pressing or rolling of their fingerprints. That is the role of the trained fingerprint technician. To sim-ulate this, you will use your left hand to roll your right hand fingerprints and your right hand to roll your left hand fingerprints. Procedure Rolling Fingerprints 1. The recommended position to record fingerprints is for the forearm to be parallel with the floor when roll-ing them onto the fingerprint card. Based on your height, find a flat surface, such as a table or countertop, that easily allows your forearm to be parallel to the floor. Place the fingerprint card on the surface so that the top row with the right hand labels is near the edge of the surface where you will perform the fingerprint rolling. Secure the top of the card to the surface with a piece of masking tape to keep it from falling off the table. Note: An actual fingerprint station will typically have a card holder to secure the fingerprint card and only expose the row being printed. 2. Remove the plastic seal and cover from the ink pad. 3. Wash your hands with soap and water. Then, dry them with a clean paper towel or towel. 4. Prepare to roll your right thumb. To do this, all other fingers should be tucked under the palm of your hand and into a fist as if you were giving a thumbs up. 5. Firmly roll your right thumb from left to right (Figure 7) over the ink pad to evenly cover the skin from one edge of the fingernail to the other, and from the crease of the first joint to the tip of the thumb. Materials Fingerprint Ink Pad Fingerprint Card Hand Lens Masking Tape *Camera (a camera phone is acceptable) *+Right Hand Fingerprints *+Left Hand Fingerprints *Paper Towel or Clean Towel *Soap and Water (for hand washing) *Surface (see Step 1 in Procedure) *You Must Provide +Discuss any needed accommodations with your instructor 45 Fingerprinting Fingerprinting Note: Pressing your thumb too hard may fill the grooves of your fingerprint with ink. 6. Use your left hand to position your right thumb over the ar-ea on the fingerprint card under the “RIGHT THUMB” label. 7. Place the right edge of your thumb print on the area so that the edge of your nail is touching the card and roll your thumb from right to left and off the card form. A quality fin-gerprint should clearly contain the ridge skin from nail to nail. This creates a rectangular fingerprint. Note: If you were fingerprinting an individual, you would stand to their left. When rolling the thumbs, you would roll them towards your body. 8. Repeat Steps 5 – 7 for your right fore finger, right middle finger, right ring finger, and right little finger in their allotted space, but roll the print from left to right. Note: If you were fingerprinting an individual, you would stand to their left. When rolling the fingers, you would roll them away from your body. 9. Wash your hands with soap and water to remove the ink from your hands. 10. Shift the fingerprint card away from your body so that the left hand row lays flat near the edge of the sur-face. 11. Repeat Steps 5 – 9 with your left hand fingerprints. Remember to use your right hand to roll your left hand fingers. 12. Shift the finger print card away from your body so that the bottom row lays flat near the edge of the sur-face 13. Take a flat print of your right thumb by pressing it flat on the ink pad. 14. Use your left hand to press your right thumbprint flat on the bottom row fingerprint card area labeled “RIGHT THUMB”. 15. Apply ink to each of your four right hand fingers. Note: An actual fingerprinting station will have an ink pad large enough to apply ink to all four fingers simultaneously. 16. Take a flat print of all four right fingers at the same time by pressing them flat on the ink pad together. 17. Use your left hand to press your four right fingers flat onto the area of the finger card labeled “RIGHT FOUR FINGERS TAKEN SIMULTANEOUSLY”. 18. Wash your hands with soap and water to remove the ink from your hands. Figure 7: Step 5 refer. The thumb, rolled from one of the nail to the other. 46 Fingerprinting Fingerprinting 19. Repeat Steps 13 – 18 with the left hand. Remember to use your right hand to press your left hand fingers. 20. When you are done taking your fingerprints, wash your hands with soap and water. 21. Use a hand lens to identify the basic pattern (arch, whorl, or loop) of each fingerprint. Record the patterns in Post-Lab Question 1. 22. Use a camera to photograph your fingerprint card. Note: You will need to download, scan, or print the photograph to be included with your lab report. 23. Use Table 1 in the introduction and a hand lens to identify minutiae characteristics. Also look for additional unique characteristics, like scars or creases. 47 Fingerprinting Fingerprinting Experiment 2: Lifting Fingerprints In this experiment, you will practice dusting and lifting fingerprints from metal and glass surfaces. LAB SAFETY: You will dust for fingerprints using a fine powder on different surfaces. Choose surfaces that are easy to clean and do not pose a concern for possible stains. Procedure 1. Place a sheet of printer paper on a table or counter top. 2. Pour a small amount of fingerprint powder onto the printer paper. 3. Rub one of your index fingers on an oily part of your face, such as your nose or cheek. 4. Press the oiled fingertip on several areas of a metal surface. 5. Put on a pair of disposable gloves. 6. Use a camera to photograph the surface before it is dusted for fingerprints. Note: You will need to download, scan, or print the photographs to be included with your lab report. 7. Lightly dip the tips of the dusting brush into the powder and generously shake the brush over the paper to remove excess dust. Note: Prints can easily be overdeveloped by using too much powder. 8. Lightly twirl the fingerprint dusting brush in a circular motion over an area where you applied a fingerprint. The twirling motion will help cover all sides of the ridge detail. To avoid overdeveloping the fingerprint, en-sure the brush does not contact the surface too much. Materials Disposable Gloves (located in your safety kit) Disposable Pipette Fingerprint Brush Fingerprint Powder 2 Lifting Tape Sheets Permanent Marker Ruler Sheet of Printer Paper *Camera (a camera phone is acceptable) *Fingertips *Glass Surface (window, bottle, etc.) *Metal surface (chair, door knob, etc.) *Skin Oil (from face) *You Must Provide 48 Fingerprinting Fingerprinting 9. Use a disposable pipette to puff air over the fingerprint to remove excess dust. 10. If the fingerprint is overdeveloped, repeat steps 7 – 9 as needed until a viable fingerprint is developed. This is a skill that requires practice. Do not proceed to the rest of the procedure until you are satisfied with the fingerprint. You only receive two sheets of lift tape in your kit, one for each surface. 11. Use a camera to photograph the revealed fingerprint. Note: You will need to download, scan, or print the photographs to be included with your lab report. 12. Peel and discard the clear plastic cover to expose the adhesive side of the lift tape. Be careful to avoid contaminating the black background with fingerprint dust. 13. Place the adhesive side of the lift tape on the fingertip area to cover the entire print. 14. Carefully remove the tape from the surface with the print by gently peeling it away from the surface. 15. Use the edge of a ruler to remove any bubbles from the tape. Use caution to keep the print intact. 16. Use a permanent marker to label the top of the tape with the date and your initials under the correspond-ing labels. Under the case # and date label write “metal.” 17. Repeat Steps 3 – 16 on a glass surface using the tape labeled “glass.” 77 Credits Credit Saferstein, R., (2013). Forensic science from the crime scene to the crime lab. (2nd ed.). San Fran-cisco, California: Pearson Education Inc. Technical Working Group on Biological Evidence Preservation. The Biological Evidence Preserva-tion Handbook: Best Practices for Evidence Handlers. U.S. Department of Commerce, National Insti-tute of Standards and Technology. 2013. www.canstockphoto.com © 2016 eScience Labs, LLC All rights reserved

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