Jack Laird Lecture Flashcards
(26 cards)
How many cases does the biology department of CFS get annually?
~13,000
How many pieces of evidence does the bio department of CFS receive annually?
> 31,000
What proportion of cases are the biology department actually called to testify about?
> 2-3%
Outline the timeline of forensic work. (8) Identify the aspects that are part of the continuum of evaluation.
Crime
Evidence gathering
(Forensic pre-assessment
Forensic examination
Interpretation of test results
Report writing
Formulation of opinions
Expert testimony)
What is evaluation predicated on?
The framework of circumstances provided to forensic scientists
What is the meaningfulness of the likelihood ratio dependent on? What is the issue with this?
Dependent on the context of the case, not known to forensic scientists
What does the offence level deal with?
Guilt or innocence
What levels of the hierarchy of propositions do forensic scientists deal with?
Activity, source, sub-source
What does the activity level deal with?
How/when evidence deposited
What is the hierarchy of propositions crucial for? (3)
Providing structured approach to evidence evaluation
ENsuring clarity and consistency in forensic reporting
Helping forensic scientists communicate their findings effectively
What does TPPR stand for?
Transfer, persistence, prevalence and recovery
What is transfer?
Movement of DNA from one person to another
How does understanding transfer mechanisms help forensic scientists?
Helps scientists determine how DNA evidence was deposited at a crime scene
What is persistence as it relates to DNA?
Ability of DNA to remain on a surface over time
What factors can affect DNA persistence? (3)
Environmental conditions
Surface type
Time elapsed
How does assessing persistence help forensic scientists?
Helps scientists evaluate the relevance of DNA to the timeframe of the crime
What is prevalence as it relates to DNA?
Commonness of DNA from different sources in a given environment
How does understanding prevalence aid forensic scientists?
Helps scientists assess the likelihood of finding DNA from various individuals at a crime scene
What is recovery as it relates to DNA?
Process of collecting and analyzing DNA evidence from a crime scene
What are effective recovery techniques essential for?
Obtaining reliable and interpretable DNA profiles
What factors can impact DNA recovery? (3)
Collection methods
Storage conditions
Lab procedures
What is the timeline of the criminal justice system?
Crime
CHarges
Trial
What is the phase of forensic testing that takes place pre-charge?
Investigative phase
What is the phase of forensic testing that occurs post-charge?
Litigative phase
