19. opinion evidence and experts Flashcards
what is the general rule for opinion evidence?
witnesses may only give evidence of facts they have personally perceived NOT evidence of their opinion
what are the exceptions to the general rule on opinion evidence?
non-experts: if made by witness as way of conveying relevant facts personally perceived by him or her is admissible as evidence of what they have perceived
experts: a statement of opinion on any relevant matter calling for expertise may be made by a witness qualified to give such an expert opinion.
what does expert evidence need to be to be admissible?
sufficiently reliable and have precise factual foundations
if admiss of expert ev questioned who is burden on?
If objection to the admissibility of expert opinion evidence is made, it is for the party proffering the evidence to prove its admissibility
what needs to be satisfied when instructing experts
that they have expertise and are of a suitable calibre. specialist knowledge, study or experience.
can judges remove expert status?
yes and limit their evidence to purely factual issues.
can police officers be experts?
yes:
on practices, mores and asspciations of gangs
evidence about accident investigation
what matters can experts be called for?
only subjects calling for expertise that lay person could not be expected to possess to a degree sufficient to understand the evidence given in the case unaided.
when are experts not required?
if the tribunal of fact can form its own opinion without the assistance of an expert / the matter is within its own experience and knowledge.
what can counsellors in SA cases do?
A counsellor should use objective language and avoid saying anything that can be construed as subjective comment or a statement of personal opinion.
what subjects often call for expertise?
variety of medical, psychiatric, scientific and technological matters, and questions relating to standards of professional competence.
can experts give opinion on ultimate issues?
yes procided that the words they use will not be the same as when issue falls to be considered by the court
Example:
psychologist may give evidence of opinion as to why the accused might be disposed to make an unreliable confession but is not entitled to assert that the confession made is in fact unreliable
how can experts be certified?
through the Expert Witness Institute. Certification assesses all the core competencies required of an expert witness and recognises those who can demonstrate excellence in report writing, discussions between experts and giving oral evidence in court
what is the duty of an expert?
- overriding duty to court
- must help court achieve OO
- give unbiased opinion on matters within their area of expertise
- actively assist court by complying with directions
- draw courts attention to questions which may be outside thier expertise
- inform all parties of any changes to their opinion from that contained in report or statement
function of expert evidence?
to furnish judge/jury with necessary scientific criteria for testing the accuracy of their conclusions, so they can form independent judgement by the application of those criteria to the facts
