Forensic Science Crime Scene exam questions and answers fully solved
The goal of crime scene investigation is to - Answersrecognize, document, and collect evidence
at the scene of a crime. Solving the crime will depend on piecing together the evidence to form
a picture of what happened at the crime scene.
Locard's Exchange Principle - AnswersWhenever 2 objects come in contact w/ one another, a
cross transfer of physical evidence can occur. The intensity, duration, and nature of the materials
in contact determine the extent of the transfer.
direct evidence - Answersfirsthand observations (eyewitness accounts, videos, confessions)
circumstantial evidence - Answersindirect evidence that can be used to imply a fact but does
not directly prove it
physical evidence (type of circumstantial evidence) - Answerssynthetic fibers, weapons, bullets,
shell casings, paint chips, documents, imprints, and prints (shoes, tires, etc.), tool marks, soils,
drugs, etc.
biological evidence (type of circumstantial evidence) - Answersbody or body parts, body fluids,
hair, leaves or other parts, natural fibers, feathers, wood
trace evidence (type of circumstantial evidence) - Answerssmall but measurable amounts of
physical or biological material found at a crime scene
ex: strand of hair, fingerprint, DNA, drop of blood, pollen, gunshot residue
The more circumstantial evidence there is... - Answersthe greater weight it carries (probability
and statistics)
class evidence - Answersnarrows evidence to a group or persons or things
- may become more individualized
individual evidence - Answersnarrows evidence down to a single person or thing
Evidence can... - Answers- prove a crime has been committed and set the scene for the
investigations
- back up witness testimony or prove it false
, - link a suspect with a victim or with a crime scene
- determine the identity of people associated with a crime
- allow investigators to reconstruct a crime
The crime scene investigation team - Answers- first police officer on the scene
- backup police & possible a district attorney
- medics (if necessary)
- investigator/detective(s)
- medical examiner
- photographer and/or field evidence technician
- lab experts
All of the investigation team must wear - Answersprotective gear to prevent contamination of
crime scene
The first responding police office must make sure the scene is secure by first making sure: -
Answersall individuals in the area are safe and second by preserving evidence
the first responding police officer should: - Answers1. obtain medical assistance if needed
2. arrest suspects
3. isolate the area
a. exclude all unauthorized personnel
b. put up tape, ropes, barricades, or position guards so no one may enter/leave (keep a security
log of all who visit scene)
c. prevent loss of evidence
4. request additional needs for investigations (more officers, experts, etc.)
What should witnessed not be allowed to do? - AnswersTalk to one another, this prevents them
from working together to create a story (collusion)
The goal of crime scene investigation is to - Answersrecognize, document, and collect evidence
at the scene of a crime. Solving the crime will depend on piecing together the evidence to form
a picture of what happened at the crime scene.
Locard's Exchange Principle - AnswersWhenever 2 objects come in contact w/ one another, a
cross transfer of physical evidence can occur. The intensity, duration, and nature of the materials
in contact determine the extent of the transfer.
direct evidence - Answersfirsthand observations (eyewitness accounts, videos, confessions)
circumstantial evidence - Answersindirect evidence that can be used to imply a fact but does
not directly prove it
physical evidence (type of circumstantial evidence) - Answerssynthetic fibers, weapons, bullets,
shell casings, paint chips, documents, imprints, and prints (shoes, tires, etc.), tool marks, soils,
drugs, etc.
biological evidence (type of circumstantial evidence) - Answersbody or body parts, body fluids,
hair, leaves or other parts, natural fibers, feathers, wood
trace evidence (type of circumstantial evidence) - Answerssmall but measurable amounts of
physical or biological material found at a crime scene
ex: strand of hair, fingerprint, DNA, drop of blood, pollen, gunshot residue
The more circumstantial evidence there is... - Answersthe greater weight it carries (probability
and statistics)
class evidence - Answersnarrows evidence to a group or persons or things
- may become more individualized
individual evidence - Answersnarrows evidence down to a single person or thing
Evidence can... - Answers- prove a crime has been committed and set the scene for the
investigations
- back up witness testimony or prove it false
, - link a suspect with a victim or with a crime scene
- determine the identity of people associated with a crime
- allow investigators to reconstruct a crime
The crime scene investigation team - Answers- first police officer on the scene
- backup police & possible a district attorney
- medics (if necessary)
- investigator/detective(s)
- medical examiner
- photographer and/or field evidence technician
- lab experts
All of the investigation team must wear - Answersprotective gear to prevent contamination of
crime scene
The first responding police office must make sure the scene is secure by first making sure: -
Answersall individuals in the area are safe and second by preserving evidence
the first responding police officer should: - Answers1. obtain medical assistance if needed
2. arrest suspects
3. isolate the area
a. exclude all unauthorized personnel
b. put up tape, ropes, barricades, or position guards so no one may enter/leave (keep a security
log of all who visit scene)
c. prevent loss of evidence
4. request additional needs for investigations (more officers, experts, etc.)
What should witnessed not be allowed to do? - AnswersTalk to one another, this prevents them
from working together to create a story (collusion)
