Would it have been permissible for a defense psychiatrist to question a defendant's motive under section 29 of the Mental Health Act?

hypothetical question based on facts of case, but hypothetical question concerning motive of someone in defendant's position would have been permissible under 29]; People v. Jackson (1984) 152 Cal.App.3d 961, 968, 969 [defense psychiatrists testified that on day of stabbing, defendant's action was result of mental disease and psychotic compulsion, but could not specifically testify that defendant did not premeditate or have malice aforethought].)