Lesson 1 - Evidential Considerations Flashcards
(19 cards)
1
Q
Types of potential evidence at crime scenes
A
- Fingerprints
- DNA
- Shoe Impressions
- Hairs and Fibers
- Marks
- Paint and Glass
2
Q
Fingerprints - Explain and how to preserve
A
- Made from an individual’s sweat deposits
- Substances: saliva, blood, oil or grease
- Surfaces: grass, metal, wood, plastics, ceramics and paper
- If prints are on an object, assess whether it has to moved due to weather (should be in a dry area)
- Tell Scene Examiner if object is moved
3
Q
DNA - Explain and how to preserve
A
- Deoxyribose-Nucleic Acid
- Genetic information from one generation to next
- Unique (apart from identical twins)
- Retrieve from virtually any surface
- Kept away from likely contamination sources
- Use gloves and don’t talk or cough over area
4
Q
Shoe Impressions - Explain and how to preserve
A
- Variety surfaces, hard or soft
- Not always obvious
- A box or similar to cover them when outside
- Ask occupier not to clean them prior to examination
5
Q
Hair and Fibers - Explain and how to preserve
A
- Transferred during physical contact
- Often used to prove contact between two individuals in rape, murder, and assault cases
- Seize clothing from victim, witness or suspect
- Each item should be placed in separate bags
- If examining car, do not sit in
6
Q
Marks - Explain and how to preserve
A
- Occur when two surfaces come into firm contact with each other
- Forensically almost any marks can be link to the item that made them
- Don’t put anything into the mark
- Cover mark if there are adverse weather conditions
7
Q
Paint and Glass - Explain and how to preserve
A
- Used to link suspects to crime scenes
- Strength of evidence will depend on the material concern and case
- Paint often presents in minute flakes or smears on clothing, vehicles or tools
- Should be recovered by seizing clothing and footwear
8
Q
What is contamination?
A
- Interference, often caused by unwittingly by humans, animals or other means
9
Q
Explain how contamination can impact upon a crime scene
A
- Should never visit a crime scene or victims if you have had an interaction with suspect for that offence
- Victims and suspects should be transported separately
- If contamination is shown to have occurred it can cause a misinterpretation of scene, compromise DNA evidence and lose the integrity of evidence
10
Q
State the phases of the initial actions of a crime scene
A
- APC
- Assess, Protect, Communication
11
Q
Assess Phase
A
- Identify the exact crime scene
○ Where is it
○ What is it
○ How big is it - Assess the situation quickly and carefully, to identify most appropriate action
- First duty at scene: Preserve life (always first priority)
- If victim is alive: First aid
- Observe scene and where the victim is
- Removal of victim creates minimum disturbance
- Common Approach Path
- Record all facts and report them to supervisor or SIO
- Hospital procedure thereafter
- Avoid taking obvious route of offender
12
Q
Common Approach Path
A
- Route in and out of a crime scene
- Everyone should take the same routes
13
Q
Protect Phases
A
- Second duty at scene: Protect the scene against people and the elements
- Cordon off area as soon as practicable (with tape)
- If indoors, the cordon area should possible probable entry and exit paths of offender
- Can make areas big and later minimise area
14
Q
Communication Phase
A
- Key to effective investigation and professional crime management
- Asking questions
- Establishing facts
- Giving advice and assistance
- Report the full situation at the scene to your control room
To ensure you receive the appropriate assistance
15
Q
First officer entries made in notebook
A
- Time called to scene and arrival time
- Persons present on your arrival
- Weather conditions
- Exact position of key pieces of evidence, e.g., a body, a weapon, etc
- Exact position of objects in and around the scene
- Signs of a struggle
- Location of keys
- Were doors and windows open or closed, locked or broken
- Foot impressions
- Marks left by a vehicle
- Rough sketch of crime scene
- Odours (e.g., cigarette smoke, perfume or aftershave)
- Lights on or off
- Details of other people involved at this stage, such as doctors or paramedics should be noted. This will enable any fingerprints, footprints or DNA they have left to be eliminated
- Time of arrival or departure of personnel at a scene
16
Q
When is a Scene Entry log completed
A
- Serious incident once a cordon is in place
- Available within the police equipment in police vehicles
- Should be logged when guarding a crime scene
17
Q
Scene Entry Log information
A
- Details of the officer keeping the log
- Reason for entering crime scene
- Movements/actions at crime scene
- Arrival and departure time (including the Loggists)
- Names of personnel attending at scene
18
Q
Importance of Scene Entry Log
A
- May become a production in a future case and come under scrutiny during trial
- Must be accurately completed and in full
19
Q
Examples of Health and Safety consideration at crime scenes
A
- Electrical, Structural and Fire risks within buildings particularly Cannabis cultivations being identified
- Incidents involving Chemical, Gas or Bio Hazards
- Body fluids, drugs and offensive weapons when searching persons or property
- Dealing with violent individuals
- Controlling large crowds, such as planned/unplanned protests, sporting events etc.
- Attending incidents related to natural hazards such as open water
- Operational activities during periods of severe weather
