Expert (opinion) Evidence Flashcards
*R v Turner [1975] QB 834.
there is no automatic right to call an expert
There is no general rule that psychiatric evidence is admissible to prove that a defendant is likely to be telling the truth. D was charged with murder. He admitted the killing, but pleaded provocation. He sought to call a psychiatrist to give evidence of his personality and mental condition to show that he was such a man as could not commit such an act without being provoked, and that he was therefore likely to be telling the truth. The evidence was based on information from medical records. The judge excluded it as being irrelevant and inadmissible. D was convicted of murder.
Hendry v HM Advocate 1987 JC 63
The “actual issue” rule
An accused was charged with assaulting a 67 year old man by punching, knocking him down and kicking him in consequence whereof he suffered a heart attack and died. Medical evidence disclosed that the deceased suffered from heart disease and that other stressful factors were present, and one doctor stated in evidence that he could only say on balance of probability that the assault caused the heart attack. The accused was convicted of culpable homicide and appealed.
Held, that the question of whether a causal link between the assault and the death was established beyond reasonable doubt was a matter for the jury and that there was sufficient evidence to entitle the jury to discount the other stressful factors and to be satisfied on that question; and appeal refused. Observed, that it is improper to ask an expert witness to express an opinion on an essential fact beyond reasonable doubt, that being an invitation to usurp the function of the jury.
*HM Advocate v Grimmond 2002 SLT 508
rule against Oath-Helping
The Crown then attempted to lead evidence from a clinical psychologist who worked in cases of child sexual abuse. Although she had not had any direct contact with the boys, she had studied material relevant to the case and had compiled a clinical psychology report in order to assess the credibility and reliability of the boys statements given the two stage revelations. She concluded that the statements given by the boys were both credible and reliable. The defence objected to her evidence as inadmissible arguing that the credibility and reliability of a witness was a matter for the jury.
Held, sustaining the objection and declaring the evidence inadmissible, that (1) evidence of facts affecting the credibility or reliability of a witness was generally inadmissible in Scotland
HM Advocate v A 2005 SLT 975
rule against oath-helping
(allowed it this time)
Held, repelling the objection, that (1) the jury would need skilled assistance in order to understand the complainer’s state of mind and reach a conclusion as to her credibility and reliability, and the evidence of the clinical psychologist met the conditions for the admissibility of expert evidence at common law
Objection to the evidence on the basis of the general rule against oath helping was decisively trumped by the fundamental duty of the court to ensure that the trial was conducted with fairness
*Hainey v HM Advocate 2013 SLT 525.
Expert witness - qualifications
Woman was charged with murdering baby son.
Defence wanted to lead expert evidence to show that there were possibilities that the child could have died from natural causes.
Prosecution led evidence involving “harass lines” by medical anthropologists who were not medically trained (not doctors).
Woman was convicted.
On appeal the conviction was quashed due to misdirection by the first judge.
An appeal against conviction for murder had to be allowed and the conviction quashed where the trial judge’s failure to direct the jury to disregard expert evidence given by witnesses who did not have the necessary competence and qualifications to give such evidence, and failure to carry out any detailed rehearsal in his charge of the other medical and scientific evidence at trial which might be thought to have very seriously undermined that evidence, were material misdirections resulting in a miscarriage of justice.
