His statement, “then execution or blood money is due from them both”: “execution” means retaliation, and “or” here denotes variation, not a choice. Thus, execution applies if it is chosen, or blood money if the victim’s heirs pardon it.
His statement, “from them both,” means from the killer and the one who compelled him, because the compeller forced the matter, while the compelled person intended to kill another in order to preserve his own life. Thus, each of them was a wrongdoer, and retaliation or blood money is due from them both.
It was also said that liability rests upon the compelled person alone, because he has no right to kill another in order to preserve his own life. He should say, for example, to the one compelling him: “I will never kill him; do whatever you wish, even if you kill me.” But for me deliberately to kill a person whose life is inviolable merely because you compelled me—this cannot be. This is not among the rights of Allah which Allah has excused in cases of compulsion; rather, it is a human right. For this reason, this view is very strong.
And it was said that liability rests upon the compeller, because the compeller forced the matter and the compelled person was under necessity; had that person not compelled him, he would not have killed. Yet this reasoning is exceedingly weak when compared with the reasoning of the view that liability rests upon the compelled person, and cannot stand against it.
Thus, the correct view is that liability rests either upon the compelled person or upon both of them together. In that case, the judge should consider what is more beneficial for the people in this matter. If he executes them both, and considers that the public interest requires it, then let him do so.
This applies unless the compelled person is like an instrument. If he is like an instrument, then the blood money or retaliation is due from the compeller. By our saying, “like an instrument,” we mean, for example, that a man takes a vigorous man, holds him, and strikes another man with him, causing him to die. In that case, retaliation or blood money is due from the killer, because this person has become like an instrument and is unable to free himself.