Musannaf Ibn Abi Shayba 18:1063

Abu Bakr narrated to us, he said: Waki’ narrated to us, from ‘Ali ibn Salih, from Mansur, from Ibrahim, regarding a man who commands a man, so he kills: He said: "They are both partners." Waki’ said: "This is, according to us, regarding the sin." As for the retaliation (qisas), it is only upon the killer.