Chapter Two Intro to Forensic Science
List four situations in which a warrantless search may be justified?
(1) the existence of emergency circumstances (2) the need to prevent the immediate loss or destruction of evidence (3) Immediate control (4) Consent of parties involved
Define the chain of custody and explain why maintaining a proper chain of custody is important. What are the possible consequences of failing to maintain a proper chain of custody?
A list of all people who came into possession of an item of evidence. Maintaining a chain of custody is the best guarantee that the evidence will be admissible in court. Failure to record the chain of custody can lead to serious questions regarding the authenticity and integrity of the evidence and examinations of it.
What two diseases have sensitized the law enforcement community to the potential health hazards that can exist at crime scenes? Name three basic types of protective clothing that investigators use to guard against contamination by infectious materials at a crime scene.
AIDS and hepatitis B. Three types of protective clothing latex gloves, shoe covers, liquid repellent coveralls.
Physical evidence may be obtained from the: A.) Crime Scene B.) Victim C.) Suspect D.) All of the above E.) None of the above
All of the above
Why is it important to include a brief description of the case history on an evidence submission form?
Allows the examiner to analyze specimans in a logical sequence and make the proper comparisons.
Why should ordinary mailing envelopes not be used for packaging physical evidence?
Because the powders and fine powders and fine particles will leak out of their corners.
All of the following items may be placed in an airtight container except:
Blood stained clothing
Why should bloodstained evidence not be stored in airtight containers? What is the best way to store such evidence?
Bloodstained materials should not be stored in airtight containers because the accumulation of moisture will encourage the growth of mold which can destroy evidential value in blood.
What is a substrate control and why is it important?
Consists of uncontaminated surface material close to an area where physical evidence has been deposited. Ensures that the surface on which a sample has been deposited does not interfere with lab tests.
What information must be included in any notes taken at the crime scene.
Crime scene notes must be detailed written description of the scene with the location of physical evidence recovered. They must also identify the time at which an item of physical evidence was discovered by whom, how, whom it was packaged, marked and where it was sent to.
The evidence collector is not concerned with:
Determining the natural variations
What is a rough sketch and what information must it accurately reflect?
Draft representation of all essential information and measurements at a crime scene. Must accurately depict the dimensions of the crime scene as well as all recovered items.
The obligation to maintain the integrity of evidence belongs to which of the following? A.) The first officer B.) The forensic scientist C.) The prosecutor D.) The evidence clerk E.) All of the above
E.) All of the above
Describe a druggist fold and explain why it is a superior way to package small amounts of trace evidence.
Folding one end of a piece of paper over one third and then folding the other end one third over that and repeating this process on the other two sides. This produces a closed container that keeps the specimen from falling out.
What is the most important prerequisite for photographing a crime scene? Why is this so critical?
For the scene to be in unaltered condition. Objects at the scene that have been removed, been added, or changed positions, the photography will not be admissible as evidence at trial.
Which of the following search patterns can be performed effectively by one person?
Line and Spiral
The 1978 supreme court case that related to the impropriety of the warrantless collection of physical evidence at a homoside scene is
Mincey v. Arizona
The manner of collecting and preserving physical evidence at a crime scene is determined by the:
Nature of the evidence
List the three methods of crime-scene recording
Photography, sketches, and notes
What is a standard/ reference sample and why is it important to the criminalist?
Physical evidence whose origin is known, such as blood or air from a suspect that can be compared to crime-scene evidence. Are important because they allow the criminalist to connect evidence found at the crime scene of a crime to the suspect and/ or victim.
Why is it important to package items of physical evidence in separate containers?
Prevents damage through contact and cross contamination.
What is the first critical step in crime-scene investigation? Why is this step so important?
Step 1: Securing and Isolating the scene Anyone who enters a crime scene potentially could destroy physical evidence important to the investigation.
Besides the crime itself, what locations must investigators search?
The areas searched must include all probable points of entry and exit used by the criminal (s).
What items from deceased victims must be collected submitted to the crime laboratory.
Victims clothing fingernail scrapings head and pubic hairs blood bullets hand swabs vaginal/anal/oral swabs
The relative value of laboratory test results is almost always dependent on the:
Way the evidence is collected and presented for examination.
What is the best way to maintain the integrity of evidence that is collected and submitted to the crime laboratory?
When the item is kept in its original condition found at the crime site.
How does the textbook define physical evidence?
is any object that can establish that a crime has been committed or can link a crime and its victim or a crime and its perpetrator
What is the main objective in collecting and packaging physical evidence?
prevent any change in the evidence between the time it is removed from the crime scene and the time it is received in the crime lab.