Unit 1 test review: Forensic Science
1. What is the definition of forensic science?
2. Why has there been such a rapid growth of crime labs in recent times?
3. What type of work is done in the biology lab? The toxicology lab? The physical
science lab?
4. What is the Frye standard? How does it differ from the Daubert rule?
5. What are the qualifications of an expert witness?
6. How should an investigator go about gathering evidence at a crime scene?
7. What is the “CSI Effect?”
8. What are the responsibilities of the first officer on the scene?
9. What should a photographer try to include when photographing a body?
10. What should be included on a rough sketch of a crime scene?
11. How would you package the following evidence: blood swabs, glass fragments,
debris from a arson scene.
12. What determine how successful a criminal investigation is?
13. What is chain of custody and whose responsibility is it to maintain it?
14. What is a standard reference sample?
15. What is rigor mortis?
16. How can you determine if a body has been tampered with after death?
17. What steps are involved in recording a crime scene?
Unit 1 test review: Forensic Science
1. What is the definition of forensic science?
Application of science to the criminal and civil laws that are enforced by
police agencies in a criminal justice system
2. Why has there been such a rapid growth of crime labs in recent times?
1. the fact that the requirement to advise criminal suspects of
their constitutional rights and their right of immediate access
to counsel
2. the staggering increase in crime rates
3. the fact that all illicit-drug seizures must be sent to a forensic
laboratory for confirmatory chemical analysis before the case
can be adjudicated in court
4. the advent of DNA profiling
3. What type of work is done in the biology lab? The toxicology lab? The physical
science lab?
Biology lab
- Identify and perform DNA profiling on dried bloodstains and
other body fluids
- Compare hair and fibers
- Compare and identify botanical materials such as wood and
plants
Toxicology lab
- Examines body fluids and organs to determine the presence
or absence of drugs and poisons
- Determines the alcoholic consumption of individuals
Physical science lab
- Drug identification
- Soil and mineral analysis
- Examination of trace physical evidence
4. What is the Frye standard? How does it differ from the Daubert rule?
First, both set the guidelines for determining the admissibility of
scientific evidence into the courtroom.
Frye vs. United States:
established the principle that questioned procedures, techniques, or
principles must be “ generally accepted” by a meaningful segment of
the relevant scientific community before they are admissible as
evidence at trial.
Daubert vs. Merrell Dow Pharmaceuticals, Inc.:
The Supreme Court asserted that “general acceptance”, or the Frye
standard, is not an absolute prerequisite to the admissibility of
scientific evidence under the Federal Rules of Evidence. According to
the Court, the Rule of Evidence assign to the trial judge the task of
ensuring that an expert’s testimony rests on a reliable foundation and is
relevant to the task at hand.
5. What are the qualifications of an expert witness?
Must possess a particular skill or has knowledge in a trade or profession
that will aid the court in determining the truth of the matter at issue
This knowledge may be acquired experience, training, education, or a
combination
6. How should an investigator go about gathering evidence at a crime scene?
1. The integrity of evidence is best maintained when the item is
kept in its original condition as found at the crime site
2. No types of trace evidence should be removed from garments,
weapons, or other articles
3. Use good judgment in removing and packaging the items
a. If adhering to a large structure, remove specimen with a
forceps or other appropriate tool
b. Bloodstain: scrape the stain, transfer the stain to a
moistened swab or cut out the area
4. Each item of physical evidence collected at a crime scene must
be placed in a separate appropriate container to prevent
damage through contact or cross-contamination
7. What is the “CSI Effect?”
The dramatization of forensic science on television has led to the public
to believe that every crime scene will yield forensic evidence and
produces unrealistic expectations that a prosecutor’s case should
always be bolstered and supported by forensic evidence.
8. What are the responsibilities of the first officer on the scene?
Preserve and isolate the crime scene
Concern with personal safety and the well being of any victims
Efforts made to obtain medical assistance for individuals in need
9. What should a photographer try to include when photographing a body?
Photographs must be taken to show the body’s position and location
relative to the entire scene
Close-ups photos depicting injuries and weapons lying near the body
are also necessary
After the body is removed from the scene, the surface beneath the
body should be photographed
10. What should be included on a rough sketch of a crime scene?
Contains an accurate depiction of the dimensions of the scene as well as
all the recovered items of physical evidence and their exact location,
shows important features of the crime scene.
Objects are located in the sketch by accurate distance
measurements from two fixed points, such as the walls of a room, using
a tape measure.
All items are designated by a letter or number and a legend made on
the sketch.
A compass could also be noted.
11. How would you package the following evidence: blood swabs, glass fragments,
debris from an arson scene.
Blood swabs
- Air-dry and pack in clean paper or an envelope with sealed
corners
Glass fragments
- Forceps and unbreakable plastic pill bottles
- Wrap each piece separately in cotton and pack in sturdy
container to prevent shifting and breakage
Debris from an arson scene
- Sealed in airtight container to prevent the evaporation of
volatile petroleum residues.
- New paint cans or tightly sealed jars
12. What determine how successful a criminal investigation is?
1. Expert witnesses
2. Care taken of evidence
3. Prosecution/conviction/innocence
13. What is chain of custody and whose responsibility is it to maintain it?
A list of all people who came into possession of an items of evidence
Responsibility is that of the investigators and should be kept to a
minimum
14. What is a standard reference sample?
It is the physical evidence whose origin is know, such as blood, or hair
from a suspect, that can be compared to crime-scene evidence
It is important because they allow the criminalist to connect evidence
found at the scene of a crime to the suspect and/or victim
15. What is rigor mortis?
A medical condition that occurs after death and results in the stiffening
of body parts in the position they are in when death occurs
16. How can you determine if a body has been tampered with after death?
When the heart stops pumping, the blood begins to settle in the parts
of the body closest to the ground. The skin appears dark blue or purple
in these areas. The onset of this condition begins immediately and
continues for up to 12 hours after death. The skin does not appear
discolored in areas where the body is restricted by either clothing or an
object pressing against the body – liver mortis
17. What steps are involved in recording a crime scene?
Photographing
- Objects must not be removed until they are photographed
from several angles, from all entryways, and close-ups
- As items of physical evidence are discovered, they must be
photographed to show their position and location relative to
the entire scene
- If size of an item is significant, a ruler or other measuring
scale must be placed in the picture with the object as a point
of reference
Sketching the scene
- A “rough” sketch is constructed containing an accurate
depiction of the dimensions of the scene, showing the
location of all objects having a bearing on the case
- Later, a finished sketch will be drawn by a professional
draftsman
Notes
- This is a constant activity throughout a crime scene’s
processing
- Include a detailed written description of the scene with the
location of items of physical evidence recovered
o Should be a minimum of one note for each letter
assigned on the sketch key
o Should be descriptive but concise
- Should identify the time an item of physical evidence was
discovered and by whom it ws discovered
- The names of persons involved in packaging and labeling
evidence
- May be the only written source of information about the
scene and may be used months, or even years after the
scene was analyzed. So the notes must be sufficiently
detailed to anticipate this need.