The court considered the circumstances when expert evidence might be admissible as to the defendant’s ability or inability to form the mens rea: ‘Generally speaking, if a defendant is mentally defective, or otherwise comes in the last class, ’69 and below mental defective’, then in so far as that defectiveness is relevant – relevant that is to the particular case – it may be that expert evidence should be admitted about it. That is in order to enlighten the jury upon a matter which is abnormal, and therefore ex hypothesi, presumably, outside their own experience. If it is admitted it should be confined to the assessment of the defendant’s Intelligence Quotient, and to an explanation of any relevant abnormal characteristics which such an assessment involves . . Where the defendant however is within the scale of normality, albeit, as this man was, at the lower end of that scale, expert evidence, in our judgment, is not as a rule, necessary and should be excluded.’
Judges:
Lord Lane LCJ
Citations:
[1986] Crim LR 395
Jurisdiction:
England and Wales
Cited by:
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 . .
Lists of cited by and citing cases may be incomplete.
Criminal Practice
Updated: 07 May 2022; Ref: scu.227982
