What is the ruling on killing by poisoning or feeding lethal substances?
General Chapter
Al-Mughni
Book of Wounds
Primary text
If someone is made to drink poison or is fed a lethal substance, resulting in death, it is intentional homicide requiring retribution if the substance is typically lethal. If the poison is mixed into food offered to the victim, retribution is due because the act is likely to cause death. Evidence for this includes the case where a Jewish woman poisoned a sheep given to the Prophet (peace be upon him), and when Bishr bin Al-Bara' died from eating it, the Prophet ordered her killed.
Supporting text
Ash-Shafi'i, in one opinion, argued against retribution if the victim chose to eat it willingly, comparing it to offering a knife for self-harm. Some scholars suggest that if the poison was mixed into one's own food left unattended, and an unauthorized person eats it and dies, there is no guarantee as the intruder caused their own death. If the giver knew the substance was poisonous and the victim ate it willingly, it is similar to being handed a knife. If the substance was not typically lethal, it is Shibh al-Amd. If there is doubt whether it is lethal, the statement of the one who administered it is preferred regarding its lethal nature.