LECTURE 1: CRIME SCENE PROCEDURES

Question 1

What is a crime scene?

Answer 1

Anywhere that evidence may be located that will help explain the events that occurred

Question 2

Life cycle of a crime scene

Answer 2

Incident occurs -> police/emergency services notified -> first responders attend -> crime scene established -> forensic team arrives -> briefing on incident -> preliminary walkthrough -> scene recorded -> triage process of exhibits -> collection of evidence -> testing of evidence -> scene closed -> case file managed

Question 3

Crime scene players: The First Responder

Answer 3

• General duties officer, ambulance, emergency services
• Role
  o Preservation of life #1
  o Secure the scene
  o Initial documentation
  o Preservation of evidence if required

Question 4

Crime scene players: Detective/ Investigator

Answer 4

• Specialised police officer with training in investigation
  o May not always be det- low level crime may be GD officer
• Has an interest in the ENTIRE investigation
  o Your scene may be a small component in a major operation
  o Arrests, POIs, multiple scenes/MO’s
  o Carries the burden of satisfying elements of a charge

Question 5

Crime scene players: Crime Scene Investigator/ Technician/ SOCO

Answer 5

• Civilian or sworn
• Role
  o Often involved in the scene- collection, recording etc
  o Refers for testing to specialized lab
  o Case file management/oversight of full forensic investigation

Question 6

Crime scene players: Forensic Scientist/ Expert/ Criminalist

Answer 6

-	Scientist qualified with expertise in a particular (or range of) fields
o	Forensic Biologist
o	DNA
o	Entomologist
o	Botany
o	Forensic Chemist
o	Toxicologist
o	Clan lab team
o	Drug analysis
o	CBRN
o	Other
o	BPA Expert
o	Fingerprint Expert
o	Physical Evidence Expert
o	Forensic Surveyor
o	Forensic Pathologist
o	Forensic Anthropologist

Question 7

A crime scene investigation is

Answer 7

1. Thorough
2. Systematic
3. Impartial

Question 8

Objectives of a crime scene investigation

Answer 8

• Determine if a crime has been committed
  o Criminal vs civil
  o Blood with no victim?
• Discovery and documentation of all facts relevant to the complaint
• Identify and eliminate suspects as a result of collected physical and testimonial evidence
• Locate and apprehend the offender
• Maintain proper Chain of Custody (CoC)
  o Ensure admissibility in court
• Testify as a witness to the collected evidence

Question 9

Evidence: Locards exchange principal

Answer 9

• Every contact leaves a trace
• LEP dictates that evidence, both physical and biological, is to be found at the scene of a crime because the perpetrator always leaves something behind by having contact with victims and objects. Similarly, they will often take something away with them which can be found on a search of their person, their garment, a vehicle, or their premises
  o Physical evidence – any item that comes from a nonliving origin – fingerprint, fibre, glass
  o Biological evidence – biologically derived – DNA, bloodstains

Question 10

Role/ value of evidence

Answer 10

1. Can prove the crime has been committed or establish key elements of the crime
2. It can establish the ID of persons associated with the crime
3. It can place the suspect in contact with the victim or with the crime scene
4. It can exonerate the innocent
5. It can corroborate the victims testimony
6. A suspect confronted with physical evidence is more likely to make admissions/confess
7. Court has become reliant on it – ‘see the CSI effect’
8. Juries expect it- the absence of evidence is not evidence of absence
9. Negative evidence (no physical evidence where expected) may provide useful information (false reports)

Question 11

Collection and preservation of evidence

Answer 11

• There are several scientific considerations
  o Physical evidence should be handled as little as possible
  o Items should be packaged separately in individual containers
  o Known or control samples are needed for comparative analysis
  o Generally, paper is the preferred method of packaging
  o Sealable, airtight containers for chemical evidence and accelerants to prevent gaseous evidence escaping
  o At all times, efforts should be made to avoid contamination
• A chain of custody is commenced at the crime scene that runs the duration of the case

Question 12

CoC shows:

Answer 12

o Who had contact with the evidence?
o When they were in contact
o What were the circumstances of them having it?
o What changes were made to it