What is the distribution of liability when multiple parties contribute to a destructive cause?

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If a group shares in a wrongful act that causes destruction, liability rests upon all of them. If two people place one stone each, and a third places one stone, and someone stumbles on all three and perishes, the diya rests one-third on the *aqilah* of each, according to the principal view, supporting Abu Yusuf’s opinion, as the cause originated equally from the three, regardless of the variation in their actions. If one person digs a well and another sets a knife, and someone falls into the well onto the knife and dies, Ibn Hamid held the digger is liable, analogous to the pusher. Ahmad (may Allah have mercy on him) ruled liability rests on both. Abu Bakr explained this by stating the digger is like the retainer, and the knife setter is like the killer, implying liability rests on all underlying causes in previous scenarios.