Crime Scene Processing Flashcards
What does ALS stand for in photography?
Alternate Light Source
Also known as FLS (Forensic Light Source)
How long have ALS/FLS photography techniques been in use?
Over 40 years
What types of evidence can ALS/FLS be used to detect?
- Fingerprints
- Fibres
- Hair
- Human body fluids
What is the first step in using an ALS at a crime scene?
Search the scene to locate/note items or areas of interest
What type of goggles are typically used when operating an ALS?
Orange goggles in lab; red and yellow are common in ALS kits
What camera settings are recommended for ALS/FLS photography?
- Orange filter on lens
- High depth of field
- Low ISO
- Timed exposure
Who created the system of identification known as Anthropometry?
Alphonse Bertillon
What year did Alphonse Bertillon create his identification system?
1882
What was the purpose of Bertillon’s Anthropometry system?
To distinguish first-time offenders from recidivists
What significant contribution did Hans Gross make to criminal investigation?
Published the first comprehensive description for using physical evidence to solve crime in 1891
What principle is Edmund Locard known for?
Locard’s Exchange Principle
What is the significance of the year 1986 in forensic science?
DNA was used for the first time in a criminal case in England
What does the acronym CFS stand for?
Centre of Forensic Sciences
What is the primary role of crime scene examiners?
- Recording, documenting, and examining the scene
- Collecting and preserving evidence
- Submitting exhibits for further examination
- Testifying in court
What does the first step ‘Learn’ in crime scene examination involve?
- Gathering information from sources
- Recognizing issues at the start
- Safety considerations
- Determining lawful authority
What is the purpose of conducting a scene walk-through?
To provide an overview of the entire scene and identify valuable evidence
What order do scenes typically get processed in?
- Photography
- Video
- Notes
- Rough scene sketch
- Scene examination
- Exhibit collection
What are the types of evidence mentioned?
- Impression evidence (fingerprints, footwear)
- DNA evidence (blood, hair)
- Physical evidence (clothing, weapons)
- Digital evidence (computers, cell phones)
What does a search warrant authorize?
The search of a place for the purpose of seizing ‘things’
What is required for an individual to give informed consent?
- The individual must consent to the search
- The individual must have authority to consent
- The individual must be aware of the search purpose
True or False: A primary crime scene is where the initial crime occurred.
True
What is the role of the Coroner under the Coroners Act?
May enter and inspect any place where a dead body is located
What is the significance of the year 2012 in forensic science in Canada?
Forensic Science in Canada report published (Hart House Report)
What is Locard’s Exchange Principle?
It is impossible for a criminal to act without leaving traces of their presence
Fill in the blank: The first U.S. crime lab opened in ______.
1924
What year did the FBI introduce computerized searches of the AFIS fingerprint database?
1996
What is the purpose of the Handbook of Forensic Evidence for the Investigator?
Provides an overview of collection and packaging requirements for items submitted to the CFS
What types of swabs are classified for submission to the CFS?
- Swabs of suspected blood (BLS)
- Swabs of drink containers (DCS)
- Weapon swabs (WPS)
- Other saliva swabs (SAS)
What are the different types of swabs classified for submission to CFS?
- Swabs of suspected blood (BLS)
- Swabs of drink containers / drinking implements (DCS)
- Swabs of partially eaten food / eating utensils (FDS)
- Other ‘saliva’ swabs (SAS)
- Weapon swabs (WPS) - Guns and Knives only
- Airbag swabs (ABS)
- ‘Other’ swabs (OTH)
This classification helps in systematic forensic investigations.
How should a swab of suspected blood be taken if the bloodstain is dry?
Use a moistened swab (distilled water)
Oversaturation can inhibit the ability to find DNA.
What is the swabbing procedure for drink containers (DCS)?
Only swab containers used for their stated purpose within the time frame of the relevant offence. A moistened swab is required.
This ensures that the collected DNA is relevant to the investigation.
What is required for swabbing utensils and partially eaten food (FDS)?
A moistened swab is required
This applies to food partially eaten and utensils used during the relevant time frame.
What items are included in saliva swabs (SAS)?
- Lipsticks
- Drug pipes
- Suspected spit
- Plastic cigarillo tips
- Cigars
These items may have come into contact with saliva and/or nasal secretions.
What must be true for weapons swabs (WPS) to be collected?
Handled weapons must have been brought to the scene by perpetrators during the commission of an offence.
This ensures that the collected evidence is directly related to the crime.
What is the procedure for swabbing airbags (ABS)?
Swab each deployed airbag and a separate swab of any other visible mucous or blood-like stains.
Results do not position occupants in a particular seat in the vehicle.
What is the purpose of the National DNA Data Bank (NDDB) in Canada?
- Linking crimes without suspects
- Identifying suspects
- Eliminating suspects when there is no match
- Determining involvement of serial offenders
The NDDB helps law enforcement agencies solve crimes effectively.
What are the two main indices of the National DNA Data Bank (NDDB)?
- The Convicted Offender Index (COI)
- The Crime Scene Index (CSI)
COI contains profiles from offenders, while CSI contains profiles from crime scenes.
When did the FBI’s Combined DNA Index System (CODIS) become fully operational?
1998
CODIS allows for the exchange and comparison of DNA profiles across various levels of law enforcement.
What is the significance of the United Kingdom’s National DNA Database?
It is the world’s first national database and contains over 4 million profiles, including DNA samples from about 5.2% of the UK population.
Established in 1995, it is the oldest and most inclusive national forensic DNA database.
What is the Interpol DNA Database also known as?
DNA Gateway
It was established in 2002 and allows member countries to submit various DNA profiles.
What should investigators do according to the summary of best practices?
- Know your authorities
- Be methodical
- Think/plan ahead
- Continually assess/reassess the scene
- Be prepared for the unknown
These practices enhance the effectiveness of forensic investigations.
True or False: The Centre of Forensic Sciences expects police/CSIs to collect negative control samples as of April 20, 2017.
False
Negative control samples are no longer required due to advancements in DNA testing sensitivity.
