Chapter 6 Study Guide Answers

Fill in the blanks and answer the following questions using pages 132 – 157 from the textbook.


1)      Unaltered Identity:

a)      What was “Smiling Gus” Winkler’s motto? "Take care of Winkler first"

b)      Who were some of Winkler’s accomplices? Fred "Killer" Burke, Al Capone, Bugsy Moran, Roger Touhy

c)      What did Winkler do to his fingerprints to try to evade the police? He had a doctor remove a narrow strip down the center.


2)      Introduction:

a)      “Every human being carries with him from his cradle to his grave, certain physical marks which do not change their character, and by which he can always be identified - and that without shade of doubt or question.  These marks are his signature, his physiological autograph, so to speak, and this autograph cannot be counterfeited, nor can he disguise it or hide it away, nor can it become illegible by the wear and mutations of time.”

b)      Who wrote the above quote? Lawyer wislon (pudd'n head Wilson)

3)      Historical Development

a)      How long ago did humans realize that the patterns on their fingertips could identify individuals?It's not at all clear

b)      What did ancient cultures use fingerprints as? markings

c)      When do the earliest recorded fingerprints date back to? 1792-1750 B.C.

d)     What were fingerprints used for in ancient China? used on all official documents

e)      When do the oldest fingerprints in Western culture date back to? 1684

f)       Who was the first to document the patterns on human hands under a microscope? Dr. Nehemiah

g)      Who was the first to note that fingerprint patterns are unique and that no two fingerprints are exactly the same? Johann Christoph Andreas Mayer

h)      Jan Evangelist Purkyn described nine distinct fingerprint patterns, including loops, spirals, circles, and double whorls.

i)       Sir William Herschel began collecting fingerprints in 1856.  He noted that patterns were unique to each person and were not altered by age.

j)        Who is credited with creating a way of identifying criminals? Alphonse Bertillon

k)      Who solved the first murder using fingerprints? Alphonse Bertillon

l)        What two individuals developed the classification system for fingerprints that is still in use today in the United States and Europe? Sir Frances Galton and Sir E. R Henry.

m)    What is Sir Edmund Henry credited with doing? He helped develop a classification system for fingerprints.


4)      What are Fingerprints?

a)      Fingerprints are raised portions of the skin arranged in connected units called dermal, or friction ridges

b)      What is the purpose of fingerprints?  How do they help us? They help us with our grip on objects that we touch.

c)      What causes us to leave behind fingerprints? When these ridges press against things, they leave a mark, an impression.


5)      Formation of Fingerprints

a)      Where do fingerprints form? in the womb

b)      When do fingerprints form? 10th week of pregnancy

c)      The creation of fingerprints happens in the basal layer, a special layer within the epidermis where new skin cells are produced.  In a fetus, this layer grows faster than the epidermis on the outside and the dermis on the inside. 

d)     Why can’t fingerprint patterns be altered or destroyed permanently by skin injuries? because the outer layer protects it


6)      Characteristics of Fingerprints

a)      How are fingerprint characteristics named?  They are named for their general visual appearance and patterns.

b)      What percentage of the total population has the following:

            Loops: 65%    Whorls: 30%   Arches:   5%

c)      Arches have ridges that enter from one side of the finger print and leave from the other side with a rise.

d)     Whorls’ look like a bull's eye with two delta (triangles).

e)      Loops enter from either the right or the left and exit from the same side they enter.

f)       What are the two things a forensic examiner looks for on a fingerprint? core and deltas

g)      Briefly explain how a ridge count is conducted: An imaginary line is drawn from the center of the core to the edge of the delta. Ridges in between are counted.

h)      Every individual, including identical twins , has a unique fingerprint resulting from unique ridge patterns called minutae because the details are so small.

i)        There are about 150 individual ridge characteristics on the average full fingerprint.

7)      Types of Fingerprints

a)      There are 3 types of prints found by investigators at a crime scene.

i)        Patent prints or visible prints, are left on a smooth surface when blood, ink, or some other liquid comes in contact with the hands and is then transferred to that surface.

ii)     Plastic prints are actual indentations left in some soft material such as clay, putty, or, wax.

iii)    Latent prints hidden prints are caused by the transfer of oils and other body secretions onto a surface. 

b)      How can latent fingerprints be made more visible? Fingerprints can be made more visible by dusting with powders or making the fingerprints in some way more visible by using a chemical reaction.


8)      Fingerprint Forensics FAQs

a)      Who was known as Public Enemy Number One? John Dillinger

b)      How did he change the appearance of his fingerprints? He put acid on his fingertips, technique he learned from those working in the Pineapple fields.

c)      Is fingerprinting flawless? No Explain: Humans input and analyze the information, and humans make mistakes.

d)     What percentage of examiners made false-positive identifications in the 1995 testing? 20%

e)      What must be done to prevent false convictions and to maintain the integrity of fingerprint science? Results need to be checked and double checkedto prevent false convistions and maintain the integrity of fingerprinting science.

f)       Prior to the use of computers in the year 1987  it would often take 3 months to find a match for a fingerprint with a database because getting a match with a fingerprint found at a crime scene and one stored required manuel search.

g)      What does the acronym IAFIS stand for and what service does it provide? IAFIS stands for Integrated Automated Fingerprint Identification Systems. It provides digital, automated fingerprint searches, latent searches, electronic storage of fingerprints and test results.

h)      How long does it take to get results back from the AIFIS laboratory? 2 Hours

9)      Latent Fingerprints

a)      Explain the process behind lifting a latent fingerprints off of a solid surface such as a glass: Dusting the surface with a carbon powder. Tape is then used to lift and preserve the fingerprint. The tape with the fingerprint is then placed on an evidence card.

b)      What must be done at a crime scene before lifting a fingerprint with tape? Photograph the print before it is lifted.

c)      What must be done to recover a print from a surface that is not smooth and hard? requires the use of different chemicals.

d)     Fill in the chart below:



Latent Print




 purple-blue print

Cyanoacrylate Vapor


 Household items: plastic, metal, glass, and skin

 White print

Silver Nitrate


 Wood or Styrofoam

 Black or Reddish-brown print (under UV light)

Iodine Fuming


 paper, cardboard, and unpainted surfaces

 Brownish print (fades quickly), must be photographed or sprayed with a solution of starch



10)  The Future of Fingerprinting

a)      What resolution is now available for scanning fingerprints? 500-1000 dots per inch.

b)      What research is Dr. Sue Jickells doing? Dr. Sue Jeckell's  is doing research to ask how things criminals may touch, such as explosives, cigarettes and drugs, can leave behind traces on the skin.

c)      What other technologies are being developed for using physical features to identify people?retinal petterns in the eyes, facial patterns, and patterns in the veins in the palm of the hand


***Be sure to read the “Case Studies” for Pedro Ramon Velasquez and Stephan Cowans as well as the “Careers in Forensics” bio for Peter Paul Biro.***