Who is believed regarding the perpetrator's mental state (insanity vs. sanity) when challenged?
General Chapter
Al-Mughni
Book of Wounds
Primary text
If the perpetrator claims he committed the act while insane (*majnun*), and the guardian denies the insanity, the perpetrator's statement is accepted along with his oath, provided that a prior state of insanity is known for him. If no prior state of insanity is known, the guardian's statement is accepted because the default state is soundness (*salama*). Similarly, if insanity was known but it is established that it had ceased before the killing, the guardian’s statement prevails.
Supporting text
If insanity is known to have existed, the perpetrator's claim of insanity at the time of the act is accepted with an oath, as he is more knowledgeable about his own condition. However, if it is established that the insanity had ceased before the act, the guardian's statement prevails because the default is soundness.