How much is the blood money (diyya), and how does the killer, who poisoned his relative, pay it, given that he is distraught and remorseful for his act, and does not know what to tell his brothers about the blood money?

If someone kills another with poison, the ruling differs based on the condition of the victim and their knowledge of the poison:

1. The victim is an undiscriminating child or insane: If the perpetrator gives them poisoned food and they die, retribution (qisas) is obligatory for the perpetrator if it is known that the poison is likely to kill.

2. Coercing a sane adult: If the perpetrator coerces a sane adult to eat poisoned food and the coerced person does not know it is poisoned, then retribution (qisas) is obligatory for the perpetrator. However, if the coerced person knows about the poison, there is no retribution (qisas).

3. Forcing poison down the throat: If the perpetrator forces poison down the victim's throat, retribution (qisas) is obligatory even if the victim is an adult, because the victim has no choice in this situation.

4. Offering poisoned food to a sane adult without coercion:

If the eater knows about the poison: There is no retribution (qisas) and no blood money (diyah), because they killed themselves.

If the eater does not know about the poison:

Shafi'is: No retribution (qisas), but rather blood money (diyah) for semi-intentional killing, and another opinion states that retribution (qisas) is obligatory.

Malikis and Hanbalis: Retribution (qisas) is obligatory, because it is considered a killing that is likely to occur.

Hanafis: No retribution (qisas) and no blood money (diyah), and the perpetrator is to be disciplined (ta'zeer).

The jurists have differed on this issue due to differing narrations regarding whether the Prophet, peace and blessings be upon him, killed the Jewess who had put poison for him or not. The more preponderant opinion is that retribution (qisas) is obligatory, and therefore the killer must inform the victim's guardians (awliya' al-dam) so they can choose between retribution (qisas), blood money (diyah), or forgiveness.