Full legislation
s.3
Incompetency from immature age or unsoundness of mind
persons of unsound mind, who, at the time of their examination, appear incapable of receiving just impressions of the facts respecting which they are examined or of relating them truly; and no person who is known to be of unsound mind shall be liable to be summoned as a witness without the consent previously obtained of the court or person before whom his attendance is required.