This is an extract of our Opinion Evidence document, which we sell as part of our Evidence Law Notes collection written by the top tier of University Of Otago students.
The following is a more accessble plain text extract of the PDF sample above, taken from our Evidence Law Notes. Due to the challenges of extracting text from PDFs, it will have odd formatting:
Evidence: 10th August: OUTLINE 7: OPINION EVIDENCE: Really a codification of the common law - Adams ED14. Crystallising the common law, making it worthy of argument. Basic idea is that we dont want witnesses' opinions too much, we want them to relate the facts. It is then up to the jury to infer opinions etc. General rule, s23 - stated in terms of a prohibition: witnesses shall not give evidence of an opinion, unless the judge permits it - lay opinion (s24) or expert opinion (s25). S25 is the substantial helpfulness test unless it reaches that level, there is a good chance that the fact finder will be mislead by expert opinion. "opinion" defined in s4 - means a statement of opinion that tends to prove or disprove a fact. If it mattered in a case, what opinion did someone hold, it wouldn't be covered by this section? If you're just trying to put in evidence to show that someone had an opinion, not proving a fact by its contents, it might not be covered by this section. R v Konia HC
- Cop speak - It appeared he was trying to hide, he was noticeably nervous, he seemed relieved when we left. Judge said all those things were opinions, give us facts. Lay Opinion: s24 - they will let in opinion evidence if it is necessary to enable the witness to communicate, or the fact finder to understand what the witness saw, heard or otherwise perceived. For example, identification. Classic legal analysis is that evidence of an identification is really no more than an opinion, because all you are really doing is "i think its the man". Aldwell v Police HC
- Driving around with a car that is noisily and significantly louder than the vehicle's original exhaust system
- Bring a cop to court, and he says "I heard it, it was well in excess of the standard exhaust of the car." Evidence was allowed in. Cop giving evidence on the ultimate issue in the case - normally a witness is not allowed to give such evidence, and there is lots of case law to support this. In terms of expert opinion, there is no prohibition on an expert giving an opinion on the ultimate issue in the case, and even a lay person is able (sometimes) to give an opinion on the ultimate issue. Outlines some categories - what classes of evidence are lay witnesses able to give evidence on. Age, drunkenness, handwriting identification, bodily condition, overheard noise was consensual sex. R v Bain Defence before the trial running through all the evidence they didn't like. Raised opinion evidence quite a bit - One cop said "Bain, when we arrived, was not particularly distressed.". Excluded because it was an opinion. Break it down - absence of typical signs of distress, for example. Defence not successful in other opinion evidence: Ambulance drivers etc - "He had stopped shaking, he was no longer tense, he made a half hearted attempt to get up." Bain relatives were allowed to say that David appeared "collected and relaxed", because it fitted into s24.
S24 if the opinion is necessary for the witness to communicate, or the fact finder to understand - look at these tests and think "is it going to help the fact finder? Is this the only way we can communicate?" Expert Opinion: Can get expert evidence in if you can convince the judge that it will substantially help the fact finder. Definition of expert in s4, "based on training, study or experience." "Expert evidence" means evidence of an expert, including evidence in the form of an opinion. R v Munro  2 NZLR 87 What the law is concerned with in setting a substantial helpfulness standard is that courts are nervous that a lot of experts seem to be 'trained seals', and some experts are brought in with no substantial scientific basis for their opinion. Also, our world is becoming increasingly technological, and we need more and more evidence from experts. Now, under the substantial helpfulness test, they are trying to make the judge a gatekeeper, and is supposed to screen evidence and determine whether it will substantially help the fact finder - this is a tough role, given that the judge may not have any experience in the area whatsoever. R v R CA130
- Involved s23(g) (we dont have this section anymore)
- Can have an expert, can say this kid shows signs that are consistent with sexual abuse Court wouldn't allowed it, legislature allowed it in s23(g), don't have it anymore. Typical complaints by the CA about experts. Gone beyond specific question in s23(g). No scientific references.
12th August: R v Eode:
- Tried to prove that two kg of marijuiana was for 'personal use' because he had pain
- Got a proffessor of pharmacology from a university who outlined the pain reducing effects of cannabis. Wouldn't allow the professor to say that it was conceivable that he could have smoked that amount - this was an issue for the jury. R v Makarore:
- Murder case
- Said he didn't have the intent to kill, and provocation was raised as well (historical note to this case) Trial judge didn't let the defence expert testify, he was so unhappy with the defence brief. He was a well respected psychiatrist. Appeal judge said the trial judge was correct to reject the defence expert. The psychiatrist was coming up with a theory - the accused had been raised in a subculture of violence, so that he was so used to it, and could no longer have an intention to kill. Said he had this special characteristic because of the way he was raised. Didn't allow, because the opinion wasn't based on any facts. No support from other experts for this theory that the psychiatrist was trying to run. Court was concerned that this guy had a hobby horse and was trying to run it by the court.
Buy the full version of these notes or essay plans and more in our Evidence Law Notes.