Presentation of evidence Flashcards
What distiguishes a forensic scientist from a regular scientist
They apply scientific principles fro legal purposes like investigations analysis and court testimony
What are the two main legal systems?
Adversarial system and Inquisitorial system
How do the two main systems differ?
Adversarial - lawyers control presentation, canada us system - truth is best found in cross examination
system should be efficient
Inquisitorial - judge leads fact-finding, european, aka civil system
no debate about evidence, belief truth is best discovered by cooperation in investgation
What are the three standards of proof in court?
Police: reasonable grounds
Criminal: beyond a reasonable doubt
Civil: Balance of probabilities
What is a voir dire?
A trial within a trial to determine the admissibility of evidence or qualifications of an expert usually without a jury
What are the mohan criteria for admitting expert evidence
Relevance
Necessity
No exclusionary rule applies
Properly qualified expert
What does threshold reliability mean
A basic standard of scientific support showing the opinion is based on valid principles and methods
What are some reasona. judge may exclude expert evidence even if it meets mohan criteria
Overly predjudicial, confusing, time-consuming or lacks sufficient reliability
What is the primary duty of an expert witness
To provide objective, independent, and non-partisan opnions that help court understand tehcnical matters
WHat is the difference between independence and impartiallity
Independence = no personal ties
Impartiality = unbiased attitude toward outcome or parties
Why must experts give notice before testifying
So the opossing party has time to investigate
What are the main types of evidence in court
Direct (Witness), Circumstantial (Suggest conclusions), and opinion (experts)
When is opinion evidence admissible?
Only when from qualified experts and relevent, necessary and reliable
What is confirmation bias
The tendency to focus on the information that supports a pre-existing theory or belief
What is contextual bias
When knowledge of irrelevant case details influences a forensic opinion unconsciously
Why is bias a major concern in expert evidence
It can mislead the court and contribute to wrongful convictions
What lessons have we learned from the truscott and morin cases
Misleading expert evidence, lack of impartiality, and failure to disclose can lead to wrongful convictions
What was found in the motherisk comission report
Hair testing evidence used in child protection cases was found unreliable and inadequate
what information should be included to qualify an expert witness?
academic background, training, publications, previous qualifications, and a scope of expertise
What’s the most common method of discrediting an expert
challenging the basis of their opinion through cross examination
What are three legal concepts of applied expert evidence
admissibility, reliability, weight
What is the significance of the “laying of an information” in a criminal trial
Its the formal document that intiates charges and begins the criminal trial process
During a trial, when might a preliminary inquiry be held, and what is its purpose?
it is held in serious matters to determine if there is enough evidence to commit the accused to trial
What information must be elicited during a voir dire to qualify an expert
Academics experience publications conference participation, expert testimony
Why might an expert be disqualified under R v Kovats
Due to a conflict of interest - being both the lead investigator and the expert witness whichc ompromises impartiality
Under mohan, how is relevance further assessed
Not just logical, but whether its probative value outweighs its prejudicial effect
What kinds of exclusionary rules might prevent expert evidence from being admitted
Rules against character evidence, hearsay, legal opinions, or evidence that breaches privilege
What is the investigative echo chamber in forensic science
A feedback loop where accumulating evidence and context start reinforcing particular conclusion potentially distorting objectivity
IN r v truscott what were the expert evidence errors that contributed to the wrongful conviction
Use of unreliable stomch content timing, failure to disclose relevent autopsy notes and overstatment of expert certainty
IN morin case, what type of forensic evidecen was misused
hair fiber and fiber comparisons that were overstated in terms of their probative value
