STUDY GUIDE FINAL
Chapter 1: Introduction to Forensic Science
Forensic Science- the application of science to law
Functions of forensic scientistto provide expert testimony
to exam evidence at a crime scene
to train or oversee others in collecting evidence at a crime scene
Locard’s Principle- every contact leaves a trace
Location of first crime lab- France
Examples of each
The case of Frye v. United States- general acceptance of scientific principles
Violation- anytime a law is broken
Felony- 2nd offense for trespassing, arson, possession of drugs with intent to distribute
Misdemeanor- 1st offense prostitution, 1st offense shoplifting
Infraction- speeding ticket
Chapter 2: Physical Evidence
Individual evidence: Evidence that can be associated with a single, unique
Class evidence: it can exonerate innocent suspects
Conditional evidence: Produced by a specific event or action
Pattern evidence: Blood spatter is an example
Transient evidence: Odor and temperature
Associative evidence: link the victim and suspect to each other
Chapter 3: The Crime Scene
Steps in approaching crime scene1. check the body if there is one, and get medical attention
 Personal Safety and the well-being of victims
 Preserve and Isolate the crime scene
 Record the crime scene

Primary responsibility of initial responder- interview with the witnesses, control
the scene
Packaging of blood evidence- dried before packaging to prevent mold and mildew

How many hours can it stay in plastic container before it is contaminated? 2
Chain of custody- Every person who handled the evidence must be accounted for on
the written record

must be followed or the evidence may not be admitted into court
Spiral search- May move inward or outward; best used where there are no physical
barriers
Strip search- Best in large, outdoor scenes
Grid search- Basically a double-line search; effective, but time-consuming
Zone search- search pattern breaks the area down into smaller sectors
Coroner vs. medical doctor:

How many states is the coroner ALSO a medical doctor? four

What states? Louisiana
Cases: Mark Winger, Jeffrey MacDonlad
Winger- convicted based on expert testimony from a visual information specialist.
MacDonald- the chain of custody was broken resulting in a delay in the trial
Chapter 4: Fingerprints
Friction ridges- located on epidermis part of skin
Be able to identify the following print patterns:
Plain Arch
Tented Arch
Double Loop
Central Pocket Whorl
Plain Whorl
Accidental
Ulnar Loop
Radial Loop
Cases you should study: Mark Winger Case
Winger- convicted based on expert testimony from a visual information specialist.
Jennings- The first homicide case in North America involving fingerprint evidence
occurred at his murder trial
Hamm Kidnapping Case- The first time silver nitrate was used successfully to visualize
latent prints
Methods to visualize prints: (what do they react to?)
iodine fuming- particularly useful for visualizing prints on porous surfaces, reacts
with oils and fatty deposits to produce a brown residue that can be used to visualize
fingerprints
ninhydrin- particularly useful for visualizing prints on porous surfaces
powders- particularly useful for visualizing prints on porous surfaces
cyanoacrylate- “superglue fuming”
Chapter 5: Hair
Trace Evidence- Physical evidence found in small but measurable amounts
False Positive Test- A test result that comes out positive when it should not
Cuticle- Tough, clear outside covering of the hair shaft
(examples of each)
Coronal:mouse
spinous: cat
imbricate: human
Cortex- Middle layer of the hair shaft that provides strength
Anagen Phase- Period of hair growth in the hair cycle averaging 3-5 years
Medulla- The spongy interior core of hair that gives flexibility
Telogen Phase- Final phase in hair growth resulting in hair loss
Catagen Phase- Intermediate period of hair growth lasting three weeks
How much will hair grow in one month? 1 cm
Chapter 6: Fibers
Collection of fibers
- Brushing: used for collection of fiber evidence
- Vacuuming: used for collection of fiber evidence
- Adhesive tape: used for collection of fiber evidence
Fabrics: made from twisted filaments
Cases: Wayne Williams
- Fibers found in Chevrolet station wagon
- Convicted of two murders
- 28 pieces of microscopic evidence were found on the victims
- 19 fibers were linked to more than one victim
Chapters 7 and 8: Drugs and Toxicology
acutely toxic- occur almost immediately upon exposure
Drug- A natural or synthetic substance designed to affect the suspect psychologically pr
physiologically
Toxin- A life threatening material
Toxicology- The study of adverse effects of chemicals or physical agents on living
organisms
Control- A sample of known composition w/out any material to be compared
LD50- The dose that kills 50% of the test population
Schedules (examples for each)
I- High potential for abuse; heroin, LSD, ecstasy (MDMA), marijuana
II- Currently accepted medical use with severe restrictions; cocaine, morphine, amphetamines,
Ritalin, PCP, opium
III- Lower potential for abuse ; Barbiturates, anabolic steroids, and ketamine
IV- Abuse may lead to limited psychological or physical; other stimulants & depressants, valium,
Darvon, librium, phenobarbital
Include examples of each,
what effect it has on the
body
V- Lower potential for abuse relative to drugs in VI; codeine found in cough medicine
Hallucinogen- hallucinogen
Stimulant- speed up CNS; Ritalin, amphetamines
Narcotic- Induce a state of sluggishness, codeine, heroin. morphine, oxycontin
Depressant- Slow down the CNS; alcohol, inhalants
Tests: which drugs do these reagents test for?
Duquenois-Levine- marijuana
Cobalt thiocynate- amphetamines
Van Urk- LSD
Dillie-Koppanyl- barbiturates
Marquis- heroin
Cases: Tylenol murders- killed 7 people
Chapter 10: Serology
Antiserum- blood serum containing specific antigens
Antigen- protein found on the surface of a red blood cell that determines blood type.
Platelets- Responsible for blood clotting
Hemoglobin-contsained in the erythrocytes
Terminal Velocity- The greatest speed to which a free falling drop of blood can
accelerate in the air
Bloodstain Transfer- When a bloody object comes into contact with a surface and leaves
a patterned blood image on the surface.
Cast-Off- Blood that is thrown from an object in motion
Angle of Impact- Angle at which blood strikes a target surface
Swipe- Wet blood is transferred to a surface which didn’t have blood
Void- An absence of stains in an otherwise continuous bloodstain pattern
Wipe- A non-blood bearing object moves through a wet bloodstain, altering the
appearance of the original stain
Area of Convergence- The point of origin; the spot the blow occurred
Backspatter- Blood that is directed back toward the source of energy
Point of Convergence- The intersection of two bloodstain paths, where the stains come
from opposite sides of the impact area
Contact Stain- Bloodstains caused by contact between a wet blood bearing surface and a
second surface which may or may not have blood on it
Satellite Spatter- Small droplets of blood that are distributed around a drop or pool of
blood as a result of the blood impacting the target area
Know what the following patterns looks like:
Low Velocity
Passive
Cast-Off
High Velocity
Arterial Spurt
Wipe
Medium Velocity
Transfer
Swipe
Cases: Sam Sheppard- proven not guilty because he was right-handed,
Tests:
secretor test- Acid Phosphatase Color Test, detects by placing sodium alpha
naphthylphosphate and Fast Blue B solution are on it.
luminal test- cannot distinguish between human and animal blood, uses light
Kastle-Meyer test- presumptive test, answers “is it blood”
precipitin test- To test whether a suspected blood stain is human or animal, an investigator
could use the
ABO system
O: antigens: AB antigens antibodies: none
AB: antigens: AB
A: antigens:
B: antigen
A
B
antibodies: AB
antibodies:
antibodies:
B
A
What occurs when blood type A is mixed with blood type B? agglutination
Handwriting and Document Analysis
Diacritics: crossing of t’s and dotting of i’s
Traits considered in handwriting analysis: Line quality, which indicates the amount of
pressure used by the author, Letter form, which includes curves, connections, slants, size
and angles
How many examples are needed for handwriting analysis?
3
Suggested steps to minimize a conscious writing effort on the part of a suspect?
Have suspect write a verbal statement that contains words from the original
writing
Cases: Lindberg kidnapping- Handwriting analysis aided in the investigation of which
famous crime