The defendant appealed against his conviction for murder. He admitted that he had killed his girlfriend with a hammer, but sought to bring psychiatric evidence that he was susceptible to provocation.
Held: The law jealously guards the role of the jury, or the court where it is the trier of the facts, as the judge of human nature, of the behaviour of normal people and of situations which are within the experience of ordinary persons or are capable of being understood by them
Expert medical evidence based upon observation of a witness can only be admitted if that evidence showed a recognised mental illness.
Lawton LJ said: ‘An expert’s opinion is admissible to furnish the court with scientific information which is likely to be outside the experience and knowledge of a judge or jury. If on the proven facts a judge or jury can form their own conclusions without help, then the opinion of an expert is unnecessary. In such a case, if it is just out of the scientific jargon, it may make judgment more difficult. The fact that an expert witness has impressive scientific qualifications does not by that fact alone make his opinion on matters of human nature and behaviour within the limits of normality any more helpful than that of the jurors themselves . . Jurors did not need psychiatrists to tell them how ordinary folk who are not suffering from any mental illness are likely to react to the stresses and strains of life.’ and ‘A man’s personality and mental make-up do have a bearing upon his conduct. A quick-tempered man will react more aggressively to an unpleasing situation than a placid one. Anyone having a florid imagination or a tendency to exaggerate is less likely to be a reliable witness than one who is precise and careful. These are matters of ordinary human experience. Opinions from knowledgeable persons about a man’s personality and mental make-up play a part in many human judgments.’
. . And ‘Before a court can assess the value of an opinion it must know the facts upon which it is based. If the expert has been misinformed about the facts or has taken irrelevant facts into consideration or has omitted to consider relevant ones, the opinion is likely to be valueless.’
It is a well recognised rule of evidence that ‘in general evidence can be called to impugn the credibility of witnesses but not led in chief to bolster it up’
 QB 834, (1974) 60 Cr App R 80,  1 All ER 70,  2 WLR 56, (1975) 60 Cr App R 834
England and Wales
Cited – Martin v Regina CACD 30-Oct-2001
The defendant had shot a burglar who had entered his isolated home at night. He claimed self defence, but the burglar appeared to have been shot as he retreated. A defendant is entitled to use reasonable force to protect himself, others for whom he . .
Cited – Regina v Ward CACD 1993
The court considered the admission of medical evidence to support other evidence against a defendant as to his propensity. ‘But we conclude on the authorities as they now stand that the expert evidence of a psychiatrist or a psychologist may . .
Cited – Pinfold, Mackenney v Regina CACD 15-Dec-2003
The appellants challenged their convictions for murder. The convictions had been based substantially upon the evidence of a co-accused who had admitted his part. They now challenged the admission by way of support of the evidence of the co-defendant . .
Cited – Regina v O’Brien; Regina v Hall; Regina v Sherwood CACD 16-Feb-2000
It is proper for the court to admit psychiatric evidence of a defendant’s particular readiness to make false confessions. Such evidence should however be closely circumscribed, and should include for example, that it makes the evidence gained . .
Cited – Regina v Hersey CACD 1-Dec-1997
The defendant appealed against his conviction for robbery, which had been based in part on witnesses identifying his voice. Particular concern was raised where a series of recordings had been brought together from which the witness had been asked to . .
Cited – Regina v Stockwell CA 5-Apr-1993
Expert evidence of facial comparison was admissible if the information and assessment are not otherwise available to the jury. As to Turner: ‘It is to be noted that Lawton LJ there referred to a jury forming their own conclusions ‘without help’. . .
Cited – Henry, Regina v CACD 29-Jun-2005
The defendant appealed his conviction for soliciting to murder and conspiracy to murder. An expert’s opinion now described him as of low intelligence and vulnerable to the sort of pressure of which he complained.
Held: The expert evidence had . .
Cited – Firth v Epping Magistrates Court Admn 3-Feb-2011
The defendant had faced a charge of assault in the Magistrates Court and had pleaded not guilty. She had indicated in the ‘trial issues’ form through her lawyer that her defence was self defence. The prosecutor then indicated that the charge was to . .
Cited – C v Regina CACD 6-Jul-2012
The issue in this appeal relates to the admission of evidence of witnesses, identified in her directions by the judge as expert witnesses, who gave evidence as to the impression they had formed as to the truth of complaints made to them by an . .
Cited – Gibson, Regina v CACD 11-Jan-2006
The defendant renewed has application for leave to appeal against his conviction for the murder of his daughter-in-law. The principle evidence against him was that of an accomplice. She had received letters to say that no further action would be . .
Cited – Kennedy v Cordia (Services) Llp SC 10-Feb-2016
The appellant care worker fell in snow when visiting the respondent’s client at home. At issue was the admission and status of expert or skilled evidence.
Held: Mrs Kennedy’s appeal succeeded. ‘There are in our view four considerations which . .
Cited – Challen, Regina v CACD 28-Feb-2019
Appeal from conviction for murder. The defendant had killed her husband with a hammer. She said that he had, through his controlling behaviour, abused her over many years.
Held: The verdict of manslaughter was substituted. . .
Applied – Regina v Loughran CACD 1999
The appellant had been convicted at a retrial of offences of rape and robbery. He said that there had been an attempt at sexual intercourse with the consent of the complainant, but the penetration had not occurred. He denied robbery. At the time of . .
These lists may be incomplete.
Updated: 10 April 2021; Ref: scu.190487